Physics Honors Midterm Study Guide
Which expression is a correct step in the process of adding 8.0 × 10^−2 and 6.0×10^−3 ?
(8.0+0.6) times 10^-2
Which of the following is a step in the process of dividing 8.0×10^−2 by 6.0×10^−3 ?
(8.0÷6.0)×10^[(−2)−(−3)]
A ball is rolling down a hill at +1.0 m/s . The ball is uniformly accelerating at +4.9 m/s^2 . What will the ball's velocity be 4.0 s later?
+2.1 times 10^1 m/s
What is the approximate horizontal velocity at which the boy in the diagram threw the ball?
+25 m/s
What is the spring constant for the spring in the graph?
+25.0 N/m
For this velocity-time graph, what is the average acceleration between 60 s and 120 s?
+29.4 m/s^2
You are running toward your friend at 5.0 m/s . He is running directly away from you, in a straight line, at 2.0 m/s . What is your velocity relative to him?
+3.0 m/s
A free-falling object has the velocity-time graph shown. What is the object's displacement between 2.0 and 4.0 s? Acceleration is constant.
+60 m
Cheryl runs a race on a 400.0 m circular track. She starts running east of the starting line and then circles the track and falls, stopping 1.00 m west of the starting line. Her time is 80.0 s. What was her average velocity?
-1.25 times 10^-2 m/s
The distance from New York to Tokyo is approximately 10^4 km. When it is 6:00 p.m. in New York, it is 7:00 a.m. of the next day of the week in Tokyo. Use that information to do an order-of-magnitude estimate of the speed at which the earth's surface moves because of the earth's rotation.
-10^3 km/h
A ball accelerates uniformly at −2.00 m/s^2. If the ball was initially moving at 0.20 m/s and the ball travels for 7.00 s, then what was its final velocity?
-13.8 m/s
The velocity of an object increases from −10 m/s to −15 m/s in 2.0 s. What is the average acceleration of the object?
-2.5 m/s^2
For this position-time graph, what is the average velocity for the entire curve?
-4 m/s
A baseball with mass of 0.145 kg is thrown straight down at the ground. At a particular speed, it has a drag force of 0.4 N acting on it. What is its acceleration at that time?
-7.0 m/s^2
A dogsled is moving at constant speed of 3.0 m/s in a straight line on level ground, and each of the four dogs is exerting a force of +20 N along that same straight line. What is the magnitude of the friction force on the sled and its occupants during this movement?
-80 N
You drive your car 2 km to the gas station, 4 km to the shopping mall to let your mother off, and 4.5 km back home. The trip takes 20 min. What is your velocity in m/s?
-9 m/s
2.01 The Metric System (History + Use)
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2.02 The Metric System (Base Units)
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2.04 The Metric System (Derived Units)
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2.06 Measurement + Scientific Notation
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2.07 Conversion Techniques
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2.08 Significant Figures
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2.13 Unit Test (Physical Units + Measurement Part 1)
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3.01 Graphing Physical Data
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3.02 Graphs + Data Relationships
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3.06 Problem Solving Strategies (Units)
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3.07 Problem Solving Strategies (Estimation)
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3.09 Unit Test (Graphing + Problem Solving Part 1)
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4.01 Rotation + Translation
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4.02 Frame of Reference
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4.03 Speed + Velocity
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4.04 Position-Time + Velocity-Time Graphs
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4.08 Acceleration
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4.09 Acceleration + Displacement
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4.13 Unit Test (Kinematics Part 1)
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5.01 Forces
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5.02 Inertia + Newton's 1st Law
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5.03 Newton's 2nd Law
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5.04 Mass + Weight
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5.08 Newton's 3rd Law
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5.10 Unit Test (Forces Part 1)
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6.01 The Net Forces Problem
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6.02 Resolving Vectors
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6.03 Adding Vectors
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6.07 Net Forces + Equilibrium
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6.08 Free Fall + Equilibrium
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6.09 Calculating Net Force 1
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6.10 Calculating Net Force 2
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6.11 Friction
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6.15 Unit Test (Net Forces + Vectors Part 1)
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7.01 Projectile Motion
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7.02 Uniform Circular Motion
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7.06 Angular Displacement + Torque
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7.07 Simple Harmonic Motion (Springs)
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7.08 Simple Harmonic Motion (Pendulums)
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7.12 Unit Test (Motion in 2 Dimensions Part 1)
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8.01 History of Gravitation
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8.04 Universal Gravitation
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8.05 Einstein and the Gravitational Field
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8.07 Unit Test (Gravitation Part 1)
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A dogsled is moving at a constant speed of 3.0 m/s in a straight line on level ground, and each dog is exerting a force of 15 N along that same straight line. What is the magnitude of the net force on the sled and its occupants during this movement?
0 N
On this position-time graph, what is the displacement between 30 s and 35 s?
0 m
In a car, you drive from your home 4 km to the gas station, 8 km to the shopping mall to let your mother off, and 8.9 km back home. The trip takes 20 min. What is your velocity?
0 m/s
A man pushes a 20.0 kg cart at constant speed up a hill with an 8.0° slope. What is the net force on the cart?
0.0 N
Which of the following measurements has two significant digits?
0.030 g
This figure shows the angular displacement of a pendulum on the moon (one-sixth of the earth's gravity). How long is the pendulum's string?
0.033 m
How many newtons of force are necessary to accelerate a 0.0050 kg mass at the acceleration (a) of 9.81 m/s^2 with the force expressed in the correct number of significant figures? (F=ma)
0.049 N
A position-time graph of a spring is shown here. What is the approximate amplitude of the spring's motion?
0.2 m
Which of the following is a scalar quantity?
0.2 m
Given the information in the figure, how long is the string of the pendulum?
0.20 m
If you attach a 50.0 g mass to the spring whose data are shown in the graph, what will be the period of its oscillations?
0.28 s
Suppose you are watching a video of a space mission and hear that a 2-pound hammer weighs 1 pound on the planet's surface. At approximately what rate would the hammer accelerate if it is dropped on the planet?
4.9 m/s^2
In an experiment, you calculate Newton's universal gravitation constant to be 6.34×10^−11 Nm^2/kg^2. The accepted value is 6.67×10^−11 Nm^2/kg^2. What is your percent error?
4.95%
Two rowboats on a lake are lined up, in contact, front to back in the same direction. A passenger in the rear boat pushes the front boat directly forward with a force of 40 N. How much force does the front boat exert on the rear boat?
40 N
Which of the following springs (described by its spring constant) has the shortest period when attached to a 100 g mass?
40 N/m
A 4.2 kg sled is being pulled along a snow-covered road with a rope that exerts a horizontal force of 6.0 N and, at that moment, is accelerating at 1.1 m/s^2 on level ground with friction having no significant effect. What is the normal force on the sled?
41 N
A sled whose total mass with cargo is 30.0 kg rests on ice. The coefficient of static friction is 0.20 and the coefficient of kinetic friction of 0.15. The sled is pulled horizontally by a rope at a constant speed of 0.90 m/s. How much tension force is applied by the rope?
44 N
A car travels at uniform acceleration over a time interval of 20.0 s. Its initial velocity is 11.0 m/s and its final velocity is 33.0 m/s . What distance did it travel during this time?
440 m
A golfer is 40.8 m away from the green and swings so that the ball has an initial velocity of +20 m/s. Which of the following angled clubs should he use to hit the ball onto the green?
45°
A rope pulling a sled is sloped at 15° upward at the point of contact. The tension in the rope is 50.0 N. What is the horizontal component of the force?
48 N
A 95 kg rowboat is initially at rest, until it is pulled toward the dock with a rope with a tension of 30.0 N. The dock is higher than the boat, and the rope makes an angle of 25° at the place where it meets the boat. What is the acceleration of the boat?
0.29 m/s^2
You apply 2.0 N of force to turn a 0.20 m long wrench clockwise on a pipe fitting. What is the torque that you apply?
0.40 N times m clockwise
On a spring scale that measures force, a reading shows the force of an object to be about halfway between 0 N and 1 N. Which of the following would be the most accurate measurement for the force?
0.49 N
Surfaces of copper and cast iron in contact have coefficient of static friction μs = 1.05 and coefficient of kinetic friction μk = 0.29 . Suppose a 0.15 kg smooth block of cast iron resting on top of a copper surface is being pulled with a force of 0.50 N but does not move in response. What is the force of friction?
0.50 N
How long is a pendulum with a period of 1.0 s on a planet with twice the gravity of the earth?
0.50 m
A 0.80 m wide door turns through an angle of 45°. How long is the arc of the displacement?
0.63 m
A pendulum has a period of 1.6 s. Given: T = 2π sqrt l/g What is the length of the pendulum?
0.64 m
What is the frequency of motion of a 0.50 m long pendulum?
0.70 Hz
A baseball weighing 1.42 N has been dropped from a balloon and is falling with an acceleration of 4.9 m/s^2. What air resistance force acts on it?
0.71 N
Suppose you throw a small rock over a lake so that it sails over the surface of the water. The rock has a mass of 0.090 kg and is initially moving at 8.0 m/s. How much net force does it take to bring the rock to a stop in 1.00 s?
0.72 N
A point on the tread of a tire with a radius of 0.50 m rotates one-quarter turn, which is π/2 radians. What is the linear distance of the displacement?
0.79 m
A picture is hanging from a wire whose two halves each make an angle of 45º with the horizontal x-axis, as shown. The tension in each side of the wire is 17 N. Find the vertical force that the wire exerts on the picture hook supporting it.
24 N
If you drop a penny from a height of 3.0×10^1 m in a vacuum, how fast will it be moving when it reaches the ground?
24 m/s
Suppose a planet has twice the mass of the earth and twice the earth's radius. What is the acceleration of an object in free fall on this planet?
4.9 m/s^2
This handbag exerts a force of 10 N on the hook. Which of the following values is a possible tension for each side of the cloth loop on the handbag? Each side of the loop exerts a vertical force only, not a horizontal force, on the rest of the handbag.
5 N
Which additional applied force must act on the block for the block to be at rest? Ignore friction.
5 N West
Which value indicates a dependence on the path an object travels?
5 m/s
You construct a pendulum by attaching a weight (the bob) to a string. You notice that the bob swings a distance of 2 in. every second. Estimate the average speed at which the bob moves. Assume that 1 in. is approximately 2.5 cm.
5 times 10^-2 m/s
If you walk 3.0 km to the east and then 4.0 km to the north, what is the magnitude of your displacement from your original position?
5.0 km
Which of the following measurements has three significant digits?
5.00 m
Two objects of mass 1.00 × 10³ kg each are a distance of 4.00 m from each other. If the center of one mass is regarded as being at the origin of the x-axis, and the other is centered at 4.00 m along the x-axis, what is the magnitude of the gravitational field of the two masses combined at 8.00 m along the positive x-axis? Each gravitational field acts independently. Use a free body diagram and add the vectors.
5.21 × 10^−9 m/s^2
An object moves +5.5 m . What indicates the distance?
5.5 m
Which produces the largest torque?
50.0 N perpendicular to the center of rotation at a radius of 1.0 m.
A car is moving toward the east at 50 km/h while it also moves to the north at 25 km/h . How fast is the car traveling?
56 km/h
Two movers are pushing a large crate with a force of 40.0 N each. One pushes north, the other east. What is the equilibrant force?
57 N southwest
A sled whose total mass with cargo is 30.0 kg rests on ice. The coefficient of static friction is 0.20, and the coefficient of kinetic friction is 0.15. The sled is attached to a rope, horizontally, in which the tension force is slowly increased. How much tension force applied by the rope will cause the sled to start moving?
59 N
A satellite moves around the earth in a circular orbit at a height of 6,000 km. Find its speed.
6 km/s
For this velocity-time graph, in which time interval is the object moving toward the reference point?
6 to 7 s
Jim leaves his house and begins walking to his car in a straight line. He goes 2.0 m then returns to his house to get his keys. Next, he leaves his house and travels 6.0 m to his car. What is Jim's displacement?
6.0 m
What is the value of the independent variable where the data are plotted incorrectly?
6.0 s
After you plot your data points, what kind of line should you draw for the data points?
A smooth, possibly curved, line that you judge to come closest to all the points.
What is the graph part labeled A in this diagram?
A trend line
Which of the following is an example of a rotating body?
A wheel on a moving wagon.
How is the acceleration of an object in Newton's second law related to its mass and the net force on it?
Acceleration is directly proportional to net force divided by mass.
How would you shorten the period of the spring whose motion is shown in the graph?
Decrease the mass hanging from the spring.
Which of the diagrams illustrates the correct way to add the two perpendicular vectors A and B graphically to get vector C?
Diagram (2)
R is a resultant vector that has a direction of 135°. Which pair of vectors shown can give R as a resultant?
Diagram 1
An object moves 2.5 m. Which of the following best describes this statement of motion?
Distance
Karen runs sets in basketball practice. She starts from a line, runs 2.0 m, returns to the line, runs 4.0 m, returns to the line, and runs 6.0 m. What is her distance and displacement?
Distance = 18.0 m, Displacement = +6.0 m
Force is described in terms of a derived unit. Which of the following is part of that derived unit?
Kilogram
Which is an SI base unit that makes up part of the unit of energy?
Kilogram
Which of the following base unit definitions remains linked to a physical prototype?
Kilogram
Which of the following is a metric unit of mass?
Kilogram
What are the set of equations called that can be used to quantify motion in the case of uniform acceleration?
Kinematic Equations
Which property of an object will not be changed by moving it from one place on the earth to another?
Mass
What causes gravity, according to Einstein's theory of general relativity?
Mass bending space and time.
Which of these is generally considered to have been discovered by Einstein?
Mass bends space-time.
Each of the answers below involves some kind of force. Of these, which is an example of a force acting through a distance?
Meteor falling to the Earth.
Which of the following is an SI base unit?
Meter
If you wanted to do a calculation with speed (distance/time), which base units would you use?
Meter and Second
Which of the following measurement systems originated by a government decree around 1790?
Metric
Your thermodynamics calculation involves the number of particles and a change in temperature. What SI base units would you use?
Mole and Kelvin
If the acceleration of a moving object is zero, which of the following best describes its motion?
Moving at a constant speed.
A quantity called the impulse is the average force, in newtons, multiplied by the time the force is acting. Which of the following is a unit of impulse?
N times s
Momentum is a physical quantity calculated by multiplying mass by velocity (mv) . Which of the following are equivalent units of momentum? Consult a table of units if you do not know, for example, what J is in base units. You may refer to the SI Derived Units chart on page 235 of Physics: Problems and Solutions to answer this question.
N times s
The electric field times the electric charge of a particle gives the electric force acting on the particle. The charge has units of coulombs (C) and the force is expressed in newtons (N). Suppose you are solving a physics problem in which you calculate an electric field. Which of these is a unit that your answer might have?
N/C
A baseball is batted into the air during a game. As the ball travels, it is subject to the forces of gravity and air resistance. Which of the following is directly proportional to the ball's acceleration?
Net force acting on the ball.
Which of the following is a correct definition of one newton of force?
Net force that accelerates a mass of 1 kg at 1 m/s^2.
Which of these is not evidence confirming Einstein's explanation of gravity?
Newton's third law of motion.
Which statement is equivalent to Newton's first law of motion?
No net force means no change in velocity.
A CD spins at a constant angular velocity of 4.0 revolutions per second clockwise. Which of the following statements about the CD is true?
No net torque acts on it at all.
A strong, weightless rope has a 0.20 kg mass hanging from the middle of it, as in the image. What tension force will make the rope horizontal, corresponding to θ = 0°?
No tension force can do this.
Jill multiplied mass (kg) by acceleration (m/s^2) . She obtained the units kg⋅m^2/s^2 . Was her calculation correct?
No, she should have had kg times m/s^2.
A plane is moving farther north in each second just as much as it is moving to the east in each second. What is the direction of its velocity?
Northeast
A worker pushes a large rock to the north while another worker helps by pushing it to the east. If they both exert equal force, in what direction does the rock move?
Northeast
How many uncertain digits are present when some quantity is expressed in significant figures?
One
Under what condition is the instantaneous acceleration of a moving body equal to its average acceleration over time?
Only at constant accelerations.
Which of the following is not in uniform circular motion?
Orbiting satellite that speeds up near the earth and slows down far away.
Where is the headquarters for the organization that maintains SI standards?
Paris
What is Kepler's first law of planetary motion?
Planets have elliptical orbits.
You measure the mass of a 0.500 kg (500 g) standard on your balance four times. The following measurements result: 451 g, 450 g, 449 g, 451 g. Which of the following best describes your balance?
Precise but not accurate.
You measure the mass of a 500 g standard on your balance four times. You get values of 455 g, 456 g, 454 g, and 455 g. Which of the following best describes your balance?
Precise but not very accurate.
What kind of relationship between the independent and dependent variable does this graph illustrate?
Quadratic
If an object undergoes constant acceleration, what will be the shape of the position-time graph that shows the object's motion?
Quadratic function shape
What is friction?
Resistance to motion of two surfaces in contact.
The same net force that acts on Rock A produces three times the acceleration when it acts on Rock B. What can you say about the mass of Rock B?
Rock B has one-third the mass of Rock A.
What type of motion can be seen in a hurricane that cannot be seen in the movement of a weather front?
Rotation
What type or types of movement occur in a hurricane as it moves along its track?
Rotation + Periodic Motion
Three forces, A, B, and C, act on an object simultaneously. The forces have the following x and y components: Ax = 20N, Ay = −10N, Bx = 10N, By = 15N, Cx = 0N, Cy = 5N . What are the components of the net force R?
Rx = 30N, Ry = 10N.
Which of the following measurement systems uses a base 10 system?
SI
What is the SI base unit for time?
Second(s)
Which of the following indicates the velocity on a position-time graph?
Slope
Which of the following is not an object or body?
Sound Wave
Which of the following terms is associated with Einstein?
Special relativity
Which of the following is a measurement of motion, with the derived units in m/s ?
Speed
Which of the following is distance divided by the change in time?
Speed
Which of the following is one of the main benefits of having an international system of units SI ?
Standards are based on observable, reproducible natural phenomena.
How is static friction different from kinetic friction?
Static friction involves objects that are not moving past each other.
Which object moves in simple harmonic motion?
Stretched rubber band with an attached mass.
The helium atom has two neutrons and two protons in its nucleus, and it has two electrons outside its nucleus. Which force keeps a helium atom from disintegrating into two neutrons and two hydrogen atoms?
Strong nuclear
Which of these situations involves dynamics rather than kinematics?
Studying the net forces on objects.
Which of these is an example of inertia in physics?
Tendency of a moving object to keep moving at the same speed in the same direction.
Which of these assumptions is Ptolemy's model of planetary motion based on?
The Sun moves around the Earth.
A visitor to the observation deck of a skyscraper manages to drop a penny over the edge. As the penny falls faster, the force due to air resistance increases. How does this affect the acceleration of the penny?
The acceleration decreases.
Two identical pendulums are on the surface of Mars and Earth. The period of the Mars pendulum is longer than the one on Earth. Why?
The acceleration due to gravity on Mars is less than that on Earth.
A passenger on a balloon drops a baseball over the side of the gondola. As the baseball falls faster, the drag force from air resistance increases. Which of these describes what happens to the motion of the ball from the time the ball is dropped to the time when the drag force becomes equal to the force of gravity?
The acceleration of the ball decreases.
What does it mean for the forces acting on an object to be balanced?
The net force is zero.
What is missing from this free body diagram of a sled being pulled across level ice by a dog team?
The normal force
Which of these discoveries is generally attributed to Kepler?
The orbit of Mars is an ellipse.
To actually lift off the ground, a plane must accelerate uniformly from rest to +21.0 m/s for 30 s. If the plane is taking off on a runway 5.00 km long, which of the following statements is true?
The plane has more than enough distance to take off.
Which of these best describes Earth's gravitational field?
The property at each point of space that describes the force a mass would experience.
Which of these would you include in a free body diagram for a bicycle-plus-rider taken together as the bicycle is being pedaled up a hill?
The reaction force that the road exerts on the bicycle.
A skilled adult bicyclist and his 10-year-old brother decide to have a race coasting down a hill starting from rest. If friction and air resistance have no effect, what outcome would you predict? They both use the same type of bicycle.
The result will be a tie.
What do Kepler's laws indicate happens when a satellite gets closer to the planet it orbits?
The satellite speeds up.
For the seesaw depicted in the diagram, which of the following will happen? Assume all the mass is distributed at the end of the seesaw arm and that the mass of the seesaw itself is negligible.
The seesaw will remain balanced.
For the seesaw depicted in the diagram, which of the following will happen?
The seesaw will rotate clockwise.
A small cart and one of larger mass collide and rebound off each other. The carts were initially moving with the same speed. Which one changes its velocity the most during the collision?
The small cart changes its velocity the most.
Which of these statements is true about the International Space Station in orbit around the earth?
The space station exerts a force on the earth toward the space station.
Why would an observer out in space see the earth orbiting the sun rather than the sun orbiting the earth?
The sun has much more mass than the earth.
Which feature of the diagram is an example of chart junk?
The table showing the numerical values of the data plotted.
Which of the following best describes the motion of a spinning top moving across a table?
The top both translates and rotates.
Which part of this graph is drawn incorrectly?
The trend line
Identify the error in this graph.
The trend line does not fit the data points reasonably
Which of the following is a requirement that units in a correct formula or equation must always satisfy?
The units on both sides of the equals sign, expressed in SI base units, must be the same.
Which of these would illustrate that volume is directly proportional to time in an experiment?
The volume VS time graph is a straight line raising to the right.
Which of these physical situations describes an inversely proportional relationship?
The volume always decreases as the pressure increases.
What causes gravitational force in Einstein's theory of general relativity?
The way mass bends space and time.
Which statement explains how brakes slow down a car?
They apply a torque opposite the direction of motion.
A small lab cart and one of larger mass collide and rebound off each other. Which of them has the greater average force on it during the collision?
They both experience the same magnitude of the collision force.
The same amount of net force acting on two different objects produces the same acceleration. What can you say definitely about the two objects?
They have the same mass.
Which of these requirements must be met by two physical quantities when they are added together?
They must have the same units when expressed in base units.
The item labeled 3 is an example of what part of a graph?
Tick Mark
What is the best example of the purpose of scientific notation?
To express large and small numbers.
What is the name of the part of the graph labeled 7?
Trend Line
Which of these is necessary for a reasonable order-of-magnitude estimate of the speed of a falling object?
Use numbers for the time and distance of the fall that are reasonable even if inexact.
A soccer player kicks a soccer ball at +10 m/s at an angle of 60°. What are the horizontal and vertical components of velocity of the kick?
Vx = +5.00 m/s and Vy = +8.66 m/s
Which of these is a force?
Weight
Which of these are directly proportional to each other in the same location on earth?
Weight + Mass
If you carry out an experiment measuring the weight and mass of objects in one particular location on the earth, what relation will you find between weight and mass in your measurements?
Weight is directly proportional to mass.
A baseball falls over the side of a balloon's gondola. At what point in the baseball's fall has it reached equilibrium?
When its acceleration is zero.
When is an object that has been dropped from a great height through the air closest to being in free fall?
When its velocity downward is smallest.
When is an object in free fall?
When no force but gravity acts on it.
When should you express a vector along the x-axis as a negative vector?
When the arrow representing the vector would point toward negative x.
Which statement is most nearly the same as Newton's third law?
When you push on an object, it pushes back just as strongly on you.
What is the centripetal acceleration of a jet making a turn with a radius of 0.50 km at a speed of 343 m/s?
235 m/s^2
The rate of motion of the earth at its equator is about 1,038 mi/h because of its rotation. From this information, estimate the earth's circumference using an order-of-magnitude estimate.
20,000 mi
An astronaut weighs 800 N on the surface of earth. What is the weight of the astronaut 6.37×10^6 m above the surface of the earth? Assume the radius of earth is 6,378 km.
200 N
Which of the following demonstrates a translation?
A sliding hockey puck.
What is the SI base unit for temperature?
Kelvin
What is the metric base unit of temperature?
Kelvin
Which situation best illustrates kinetic friction?
A sled pushed from one side of an ice rink to the opposite side begins to slow down as it moves.
A 2.1 kg wagon is being pulled by a rope that exerts a horizontal force of 4.0 N and, at that moment, is accelerating at 1.1 m/s^2 on level ground. Remember that g = 9.8 m/s^2 . What is the normal force on the wagon?
21 N
The terminal velocity of a tennis ball is about 21 m/s. A tennis ball is dropped from a hot air balloon. How fast will it be moving after falling for 10 s?
21 m/s
A golfer hits a golf ball with a club head angled at 30°. He swings with a velocity of +50.0 m/s . How far will the ball travel horizontally?
220 m
A balloonist drops an apple weighing 1.5 N over the side of the balloon's gondola. As it falls and increases speed, the drag force from the air upward on it increases. When the upward force is 0.7 N, what is the direction and magnitude of the net force on the apple?
0.8 N downward
A 0.013 kg rubber stopper attached to a 0.93 m string is swung in a circle. If the tension in the string is 0.70 N, what is the period of the stopper's revolution?
0.83 s
A spring has a spring constant of 100 N/m , and the mass hanging on it is 2.0 kg. What is the period of the spring's motion?
0.89 s
An outfielder throws a baseball to home plate with a velocity of +15 m/s and an angle of 40°. When will the ball reach its highest altitude?
0.98 s
To convert milligrams to kilograms, which conversion factors would you need?
1 g/1,000 mg and 1 kg/1,000 g
If the standard kilogram bar kept in Paris were subjected to a net force of 1 newton, what acceleration would it have as a result?
1 m/s^2
Which of the following represents a decimal system of measurement?
1 meter = 100 centimeters
Satellite A orbits the earth at a height 3.00 times the earth's radius. Satellite B orbits the earth at a height 2.00 times the earth's radius. What is the ratio of the period of Satellite B to the period of Satellite A?
1 to sqrt (2/3)^3
Four students report measurements of the mass of the same object. Which of the values is the least precise?
1,000 g
For the figure, during what time interval does vy become zero?
1-2s
A balloon filled with helium experiences a buoyant force upward because the helium is less dense than the air around it. Suppose a balloon with a bolt tied to it by a string is floating at a height of 200 m without changing elevation. The weight of the string and bolt is 1.0 N. What is the buoyant force acting on the balloon?
1.0 N
If a box has a length of 10.0 cm, a width of 20.0 cm, and a height of 5.00 cm, then what is its volume in m^3 ?
1.00 times 10^-3
What is the difference between 3.15 m and 2.006 m with the correct number of significant figures?
1.14 m
While spinning in a centrifuge, a 70.0 kg astronaut experiences an acceleration of 2.00 g, or twice the acceleration due to gravity on the earth. What is the centripetal force acting on her?
1.37 times 10^3 N
A bicyclist is coasting down a road that is sloped downward at an angle of 8°. The bicycle and bicyclist have a total mass of 80 kg. If the bicycle wheels roll freely, without any effect from friction or air resistance slowing the motion, how fast would the bicyclist accelerate?
1.4 m/s^2
How long does it take for an acorn to drop from the branch of a tree 10.0 m high and hit the ground, assuming no air resistance? Remember, rest is the initial velocity and it equals 0.0 m/s .
1.4 s
A block of metal weighs 60 newtons on the earth. You take it to the moon and find it weighs 10 newtons. With what acceleration will it fall on the moon?
1.6 m/s^2
A book with a mass of 0.500 kg is at rest on a frictionless table. A net force of 0.800 N then acts on the book. The net force is parallel to the surface of the table. What acceleration results?
1.60 m/s^2
The centers of two 15.0 kg spheres are separated by 3.00 m. The magnitude of the gravitational force between the two spheres is approximately what?
1.67 times 10^-9 N
A strong weightless rope has a mass m hanging from the middle of it, as shown. The tension force on each rope is 25 N, and the rope droops at an angle of θ = 20.0° . How much mass is hanging from the rope?
1.7 kg
Surfaces of copper and cast iron in contact have coefficient of static friction μs = 1.05 and coefficient of kinetic friction μk = 0.29 . Suppose a 0.75 kg smooth block of cast iron on top of a copper surface is being pulled with a horizontal force of 3.50 N. What is its acceleration?
1.8 m/s^2
A 0.50 kg hammer is taken on a space mission. What is its weight on a planet where the acceleration due to gravity is 3.8 m/s^2?
1.9 N
In an experiment, you calculate Newton's universal gravitational constant to be 7.34×10^−11 N⋅m^2/kg^2. The accepted value is 6.67×10^−11 N⋅m^2/kg^2. What is your percent error?
10%
Which force produces the smallest torque?
10.0 N perpendicular to the center of rotation at a radius of 0.25 m.
Which of the following measurements has three significant digits?
10.0 kg
A boat in a river is moving forward at 10.0 km/h relative to the water with its front end pointed perpendicular to the flow of water. The water in the river is flowing at 3.00 km/h. What is the speed of the boat relative to the river bottom?
10.4 km/h
Starting from rest at the center of a skating rink, the two skaters shown push off from each other over a time period of 1.2 seconds. What is the force of the push by the smaller skater?
100 N
What is the net force on the crate shown here?
100 N east
Which of the following has zeros that are not significant?
100 kg
A plane, starting at some point in its flight, turns and flies 200 mi in a direction of 30º north of east. How much farther north does it end up from where it started its turn?
100 mi
The crankshaft of an engine increases its spin from 1,000 rpm to 1,500 rpm in 0.5 s. What is its angular acceleration? (1 rev = 2π rad)
100 rad/s^2
The thickness of a book is 3.2 cm, measured between the insides of its covers. The highest page number in the book is 1,096. What order-of-magnitude estimate does that give for the thickness of a page of the book?
10^-5 m
Without using your spring scale, estimate the order of magnitude of the mass of your calculator in grams from what you judge to be its size, using the fact that the density of water is 1 g/cm^3. Assume that the density of water is about the same as the density of your calculator.
10^2 g
A rowboat is being pulled by two ropes tied to the front of the boat. One rope is along the x-axis direction and exerts a force of 50 N. The other is along the y-axis direction and exerts a force of 100 N. Find the magnitude of the net force that the ropes exert on the boat.
112 N
A 10.0 kg barrel is lifted by pulling up on a rope. The barrel accelerates at 1.5 m/s^2. Find the force of tension on the rope.
113 N
The length of a pendulum in simple harmonic motion is 36 m. Given: T = 2π sqrt lg What is the period of the pendulum's motion?
12 s
A 1.0 kg weight suspended from a spring is pulled to 0.25 m below its equilibrium point. If the spring has a spring constant (k) of 50.0 N/m, at what rate will the mass accelerate when it is released?
12.5 m/s^2
Two farm workers are pushing a small boulder. One is pushing north with a force of 80.0 N, and the other is pushing east with a force of 90.0 N. The boulder does not move. What is the magnitude of the horizontal component of force that the ground exerts on the boulder?
120 N
A 60 kg student in a rowboat on a still lake decides to dive off the back of the boat. The student's horizontal acceleration is 2.0 m/s^2 while in contact with the boat. What horizontal force does the student exert on the boat?
120 N toward the front of the boat.
A batter strikes a baseball of mass 0.15 kg with a force of 18 kN. What is the acceleration of the baseball?
120,000 m/s^2
How many m/s is 60.0 km/h ?
16.7 m/s
A 70.50 kg man rides a Ferris wheel with a radius of 10.3 m at a velocity of 5.00 m/s. What is the centripetal force that he experiences (F = mv^2/r) expressed with the correct number of significant figures?
171 N
Use the following equations to solve the problem. final distance = initial distance + (speed × time) df = di + vt 1.00 mi = 1.61 km For an initial distance of 11.3 km, a speed of 35.0 miles per hour, and a time of 3.00 hours, what is the final distance in km?
180 km
It takes 82 years for Uranus to circle the sun once. Approximately how far is Uranus from the sun in AU, where 1 AU is the distance of Earth from the sun?
19 AU
A 1,800 kg car is parked on a road that has an elevation angle of 7°. Suppose the coefficient of static friction of the kinds of rubber and asphalt involved is 0.65. Which is approximately the force of static friction between the tires and the road?
2,200 N
A 1,660 kg car is parked on a hill with a slope of 8.0°. Its brakes and transmission are locked in position to keep the car from rolling. The coefficient of static friction of the rubber tires on the asphalt road is 0.14. What is the force of static friction between the tires and the road?
2,300 N
How high does a rocket have to go above the earth's surface to be subject to a gravitational field from the earth that is 50.0 percent of its value at the earth's surface?
2,650 km
In the year 2081 in a shipping port on the moon, workers for Ore-Space, Inc., hoist a 500.0 kg hunk of anorthosite moon rock by a chain. (Neglect the weight of the chain.) The block is initially accelerating at 4.0 m/s. How much force is being exerted by the chain? The force of gravity on the moon is one-sixth that of earth.
2,800 N
An airplane travels directly from Washington, D.C., to Atlanta, Georgia, a distance of 850 km at a velocity of 425 km/h southwest. How long does the trip take in hours?
2.0 h
A ball accelerates uniformly at +4.0 m/s^2. If the ball was initially moving at +0.20 m/s and the average velocity was +4.2 m/s, then how long will it take it to reach the final velocity?
2.0 s
A child's sled, initially at rest, is pushed while on ice with a constant horizontal force of 20.0 N. The total mass of sled plus cargo is 20.0 kg. How fast is the sled moving after 2.00 s of being pushed? Ignore friction.
2.00 m/s
A ball moving at +3.0 m/s along a table rolls off a table and lands on the ground 2.0 m away. How high was the table?
2.2 m
A 1.3 kg cart rests on an inclined plane. The cart is released so that it is free to roll down the frictionless surface. The inclined plane is tilted by θ = 14° . Find the acceleration of the cart.
2.3 m/s^2
How long does it take an acorn to hit the ground after dropping from the branch of a tree 25 m high? Remember that g = 9.8 m/s^2 .
2.3 s
If you drop a penny from a height of 3.0×10^1 m in a vacuum, how long will it take to reach the ground?
2.5 s
The moon's gravity is one-sixth that of the earth. What is the period of a 0.25 m long pendulum on the moon?
2.5 s
The momentum of a moving car can be calculated by multiplying the car's mass by the car's velocity. Which of the following quantities could be the correctly calculated momentum?
2.7 N times s
A satellite is in geosynchronous orbit around earth, so that it stays above the same point on earth and has a period of exactly one day. Another satellite orbits earth at a distance twice as far from earth's center. What is the period of the second satellite? Assume the radius of earth is 6,378 km and the mass of each satellite is 200 kg.
2.8 days
A 2 kg bar of metal weighs about 4.4 pounds. Approximately how much does it weigh in newtons?
20 N
If you exert 10.0 N of force to compress a spring 50 cm from its equilibrium point, then what is the spring constant? Be sure to convert to meters.
20 N/m
If the ball shown in the figure lands in 2.0 s, about what height was it thrown from?
20 m
A student has just started pulling hard enough for a crate to start accelerating into motion. At that particular instant, what is the net force on the crate if the force of friction has magnitude 200 N and the applied force is 225 N?
25 N in the direction the student is pulling.
Calculate the torque produced by a force of 50.0 N applied clockwise perpendicular to the end of a bar of length 0.50 m.
25 N times m clockwise
A plane flies along a straight line path after taking off, and it ends up 220 km farther east and 110 km farther north, relative to where it started. What is the plane's displacement?
250 km
A car travels 60.0 miles per hour. What is its velocity in m/s ? (1 km = 0.621 mi)
26.8 m/s
Which is the correct answer with the correct number of significant figures to this calculation? 0.11 kg + 1.56 kg + 3.176 kg + 22 kg
27 kg
A plane flies along a straight line path after taking off, and it ends up 180 km farther east and 92.0 km farther north, relative to where it started. In what direction did it fly on the straight line path?
27° north of east
A 70.0 kg runner moving at a speed of 10.0 m/s rounds a bend with a 25.0 m radius. What is the centripetal force that she experiences?
280 N
A pitcher exerts a force on a baseball that is 30 times the ball's weight. How fast is the pitcher accelerating the ball?
290 m/s^2
What number on this diagram refers to the tick marks for the dependent variable?
3
What is the magnitude of a gravitational field at a location where an 80 kg astronaut weighs 25 percent what he would weigh on the earth?
3 N/Kg
The erg is a unit of work in units of centimeters (cm), grams (g), and seconds (s), and 1 erg=1 g⋅cm^2/s^2 . Recall that the SI unit of force is the newton (N) and is equal to kg⋅m/s^2 . You push an object 0.032 m by exerting 0.010 N of force. The work is the force times the distance. How much work have you done, expressed in ergs?
3,200 ergs
How much force does it take to bring a 1,650 kg car moving at 2.20 m/s to a complete stop in 1.1 s?
3,300 N
What is the period of the spring's motion in the position-time graph shown here?
3.0 s
What is 30,000 expressed in scientific notation?
3.0 times 10^4
In a free-fall experiment, you determine the value of acceleration due to gravity (g) to be 9.50 m/s^2 . The accepted value is 9.81 m/s^2 . What is your percent error?
3.16%
A braking car on dry pavement has a constant acceleration of −3.0 m/s^2. If the car was moving at 10.0 m/s, approximately how long would it take it to stop?
3.3 s
A 35.0 kg boy is riding an amusement park roundabout with a radius of 10.0 m. The roundabout makes one turn every 2.00 s. What is the centripetal force that the boy experiences?
3.46 times 10^3 N
A 1.00 m long pendulum in simple harmonic motion sits on the surface of Mars. It has a period of 3.26 s. What is the acceleration due to gravity on Mars?
3.71 m/s^2
A ship travels north at 15 km/h for 2 h. What is the ship's displacement in km?
30 km north
A placekicker kicks a football at an angle of 30°. At what angle will the football hit the ground?
30°
A placekicker kicks a football upward at an angle of 60° and a speed of 5.0 m/s. At what other angle will he have to kick a second ball with the same speed to reach the same distance downrange? Ignore air resistance.
30°
If the crate shown here is moving at a constant speed in a straight line, and the force applied is 310 N, what is the magnitude of the force of friction?
310 N
While racing on a flat track, a car rounds a curve of 56 m radius and instantaneously experiences a centripetal acceleration of 18 m/s^2 . How fast was the car going?
32 m/s
A mass of 10.2 kg is in a gravitational field of 3.30 m/s^2 . What force acts on the mass?
33.7 N
Two objects of equal mass of are a distance of 5.0 m apart and attract each other with a gravitational force of 3.0 × 10^−7 N . Find their mass.
340 kg
A mass of 10.0 kg is in a gravitational field of 3.50 N/kg . What force acts on the mass?
35.0 N
An airplane is flying 25° north of east at a speed of 820 km/h . How fast is it moving to the north?
350 km/h
Suppose the force on a baseball when batted is 36 kN in the direction away from the batter. What was the direction and strength of the reaction force?
36 kN toward the batter.
A car travels 10.0 m/s. What is its velocity in km/h?
36 km/h
A boy drops a ball from an observation tower. The ball hits the ground in 4.0 s. What is the ball's velocity at the time of impact?
39 m/s
How many g is 40 kg?
4 times 10^4 g
A runner moving at a speed of 10.0 m/s rounds a bend with a 25.0 m radius. What is the centripetal acceleration that she experiences?
4.00 m/s^2
Which is the correct answer with the correct number of significant figures to the following? 0.035 kg + 1.24 kg + 3.1 kg + 0.0006 kg
4.4 kg
You drop a stone down a well that is 100.0 m deep. How long will it take for the stone to reach the bottom, ignoring air resistance? Remember, rest is the initial velocity and it equals 0.0 m/s .
4.5 s
Cheryl runs a race on a circular 400.0 m track. She starts running east of the starting line and stops 20.0 m west of the starting line. Her time is 8.0×10^1 s . What is her average speed?
4.8 m/s
A 70.50 kg man rides a Ferris wheel with a radius of 10.3 m at a velocity of 3.0 m/s. What is the centripetal force that he experiences, expressed with the correct number of significant figures? The formula for determining centripetal force, in newtons, is F = mv^2/r.
6.2 times 10^1 N
A rocket ship travels 14,000 miles per hour. What is the rocket ship's velocity in m/s in correct scientific notation? 1 km = 0.62 mi
6.3 times 10^3 m/s
What is the product of 3.15 m and 2.1 m with the correct number of significant figures?
6.6 m^2
A woman pushes a grocery cart filled with groceries up a hill with an 8.0° slope. She stops to rest a distance of 30.0 m up the hill and accidentally lets go of the cart. The cart with its groceries has a mass of 18 kg. How long does it take for the cart to roll the distance of 30.0 m down the hill? Ignore friction.
6.6 s
A 60 kg student is standing motionless. Approximately how much force is the floor exerting on the student?
600 N upward
You see a bolt of lightning and hear thunder two seconds later. The speed of sound is about 343 m/s . Estimate your distance from the lightning bolt.
600 m
If you walk 3.0 km on a straight road and then find that you are 1.5 km east of your starting point and some unknown distance north of your starting point, in which of these directions did you walk?
60° north of east
The crankshaft of an engine increases its spin from 1,200 rpm to 1,500 rpm in 0.50 s. What is its angular acceleration?
63 rad/s^2
What number on this diagram indicates the trend line?
7
The reference point in this graph is a fly in the middle of the spider's web. During which time interval does the spider not move?
7 to 11 s
Use Newton's law of universal gravitation to find the speed of the International Space Station in its orbit at an elevation of 350 km. Earth's radius is 6,378 km, earth's mass is 5.98 × 10^24 kg, and the mass of the International Space Station is 304,000 kg.
7.70 km/s
A force of 100.0 N acts in a direction at an angle of 45.0° with the x-axis. What is the magnitude of the x component of the force?
70.7 N
If you throw a ball at 35° and 10.0 m/s , what is the horizontal component of velocity?
8.2 m/s
A picture is hanging from a wire whose two halves each make an angle of 45º with the horizontal x-axis, as shown. The picture and frame weigh 12 N. Find the tension in each wire.
8.5 N
You drive a car 2.0 km to the gas station, 4.0 km to the shopping mall to let your mother off, and 4.5 km back home. The trip takes 20.0 min. What is your average speed?
8.75 m/s
A free-falling object's motion can be described by the velocity-time graph shown. Approximately what is the object's position at 4.0 s?
80 m
A 90.0 kg skydiver is falling at a constant speed. What is the air resistance force acting on the skydiver?
880 N
What is the magnitude of the Earth's gravitational field at sea level?
9.8 N/kg
When a baseball is thrown straight upward, what is its acceleration at its greatest height?
9.8 m/s^2 downward
A bicyclist is pedaling along a road that is sloped upward with angle θ . At which of these road elevation angles must the bicycle wheels exert the greatest force back on the road to move the bicycle forward at the same constant speed?
9°
Which line plotted here might you obtain if x and y are inversely proportional to each other?
A
Which of these is the best example of free fall?
A baseball thrown directly upward inside a huge tube with air removed from it.
What is a free body diagram?
A diagram showing all the forces acting on an object but not its surroundings.
Which of the following demonstrates a translation?
A flying bird.
Which of the following is an example of projectile motion?
A football in flight during a field goal.
What is gravity?
A force between objects because of their mass.
What is an equilibrant?
A force that makes the net force on an object zero.
Which best describes friction in the context of Newton's laws?
A force that opposes the relative motion of two objects in contact with and sliding past each other.
Which of the following would illustrate a quadratic relation between the dependent and independent variables when graphed?
A graph of the area a of a circle vs. its radius r (a = πr^2).
Which of these should you include in every graph?
A graph title
Which of these statements is always true?
A moving object in equilibrium continues at a constant velocity.
A motorboat is turning right on a lake without changing its speed. Which of these is true about the net force acting on the boat?
A net force on the boat acts perpendicular to its velocity to change its direction.
A car accelerates from 20 m/s to 40 m/s . Which of the following statements is true?
A net torque acts on the wheels in their direction of motion.
What is a gravitational field?
A region of space-time with a property at each point determined as the gravitational force on any object divided by its mass m.
Which of the following is a difference between rotation and translation?
A rotating body moves around an internal or external axis, but a translating body does not.
Which of these follows from Kepler's laws of planetary motion?
A satellite will speed up as it gets closer to the much more massive object it orbits.
A dog that is soaking wet will typically shake its body rapidly to remove water from its fur. Which of the following is the best explanation for this?
After leaving the dog's hair, the water tends to continue moving in the same direction when the fur's motion changes direction.
What does it mean to say that the forces acting on an object are balanced?
All the forces combine to give zero net force.
What is an equilibrant?
An added force that produces equilibrium.
Which of the following best represents translational movement?
An apple falls from a tree.
What is an order-of-magnitude estimate?
An estimate of the closest power of 10.
What is a conversion factor?
An expression that states the relationship between two units.
Which of the following objects is in equilibrium?
An object that moves at constant velocity.
In the figure, a washer on a string (string not shown) moves in the circular path shown in red. Which arrow best describes the velocity of the washer at that instant in time?
Arrow B
In the figure, a washer rotates on a string (string not shown) in the circular path shown in red. Which arrow best describes the velocity vector at that instant in time?
Arrow B
In the figure, which arrow designates the angular displacement of the pendulum's motion?
Arrow B
In the figure, which arrow represents the amplitude of the pendulum's motion?
Arrow D
On a velocity-time graph, when is the object not moving?
At the point in which the line crosses the x-axis.
When is a real-life object that has been dropped over the side of a tall building closest to being in free fall?
At the start of its fall.
Which of the following is a change in displacement over time?
Average Velocity
Which of the following is a vector describing how fast an object moves over a long time interval?
Average velocity
Which line in the graph corresponds to a linear relationship between x and y that obeys an equation of the form y = mx + b?
B
Which line in the graph might you obtain if an increase in x always produces a linear increase in y?
B
What do we call the principal SI units that are used to derive all other SI units?
Base Units
Which has a weight closest to one newton?
Baseball
An archer shoots an arrow horizontally and his friend drops a penny from the same height when the arrow is released. In the absence of air resistance, which of the following happens?
Both hit the ground at the same time.
How was the gravitational constant G first determined?
By measuring the force of gravity between two objects on the earth.
Which portion of the velocity-time graph shown indicates a deceleration?
C
Which portion of this velocity-time graph indicates a deceleration?
C
An astronomer wants to measure the intensity of light coming from a star. What unit should the astronomer use?
Candela
Which of the following would be used in luminosity calculations?
Candela
Which of the following can be used to mathematically define motion in two dimensions?
Cartesian coordinates
Which of the following terms might a jet pilot use to describe a force that presses him against his seat during a high-speed turn?
Centrifugal Force
Which of the following is not a reason for converting units?
Changing meters into kilograms.
Which of the following can you do with dimensional analysis?
Check conversions between units using units only.
Which of these should you always do at the end of a calculation?
Check that the numerical answer is reasonable and the units are what you expected.
What is the car's velocity between 240 s and 300 s?
Constant
A straight line with a positive slope on a velocity-time graph indicates which of the following?
Constant acceleration in the positive direction.
Under what condition is the average velocity equal to the instantaneous velocity?
Constant velocity
What must you do to calculate a meaningful value of distance from the following equation? d final = (0.90 km) + (12.5 km)/h × (31.5 s)
Convert all times to either hours or seconds.
A fellow student reports his measurements of distance for a calculation in centimeters. How could he express that calculation using SI base units?
Convert centimeters to meters and redo his calculation.
Which of these is an example of the meaning of inertia in physics?
Crashing into another car because the brakes on your car failed.
Of the choices given, which is most likely the oldest recorded unit of length?
Cubit
The force vector A has components Ax = 5 N, Ay = −3 N. The force vector B has components Bx = 5 N, By = 4 N. What are the components of the resultant force vector C = A + B?
Cx = 10 N , CY = 1 N.
At what point on this position-time graph is the instantaneous velocity equal to zero?
D
The items labeled 6 are examples of what part of a graph?
Data Points
How would you decrease the period of the spring whose motion is shown in the graph?
Decrease the mass hanging from the spring.
Karen runs sets in basketball practice. She starts from a line, runs 2.0 m, returns to the line, runs 4.0 m, returns to the line, runs 6.0 m, and on returning stops 1.0 m in front of the starting line. What is her distance and displacement?
Distance = 23 m, Displacement = +1 m.
At what point on the position-time graph shown is the object moving toward the reference point?
E
Which of these does Newton's law of universal gravitation imply?
Earth's gravity acts on people inside a space station orbiting the earth.
What causes the centripetal acceleration of an electron in a hydrogen atom?
Electrical Attraction
Which of the four fundamental forces is mainly responsible for contact forces?
Electromagnetic force
For a spring oscillating in simple harmonic motion, at what point will the velocity of the spring be greatest?
Equilibrium point
What are the vertical bars through the data points in this graph?
Error Bars
How do you best determine whether J/m^2 and m⋅s^2/N are equivalent units?
Express them both in terms of SI base units.
At what point on the position-time graph shown is the object's instantaneous velocity smallest?
F
How do you find the instantaneous velocity on a position-time graph?
Find the slope of the tangent at any point.
Which of these forces is most similar to electrical forces?
Force between two magnets.
You turn a corner and see a ball rolling down a hill; it is rolling faster and faster as time goes by. What causes this acceleration?
Force of Gravity
Which of these is a contact force?
Force of a bat on a baseball.
What is friction?
Force opposing the motion of surfaces in contact with each other.
A rocket engine expels hot gas at a high velocity out of the back of the rocket. Which of these is the action and reaction pair?
Force that accelerates the gas and force from the gas that accelerates the rocket.
A visitor presses a button to ring the doorbell in an apartment building. Someone on the third floor responds by pushing a button mounted on the wall to release the lock and allow the visitor into the hallway. Assume the force the visitor exerts on the button is the action in Newton's third law. Which of these is the reaction?
Force that the doorbell button exerts on the visitor's finger.
You want to calculate the net force acting on an ice skater who is speeding up while skating. Which of these is a force you would not add in to calculate the net force?
Force that the skater exerts on the ground.
What is a point of view with regard to motion called in physics?
Frame of Reference
Where did the metric system originate?
France
What force causes centripetal acceleration of a car making a turn on a flat road?
Friction
Which of these is not one of the four fundamental forces of nature?
Friction
Which of these was discovered by Newton?
Gravity keeps the planets in their orbits.
Which principle was a part of Aristotle's explanation of motion that Galileo corrected?
Heavier objects fall faster than lighter ones.
What is the main topic of dynamics that is not addressed in kinematics?
How forces affect motion.
Who invented the first pendulum clock?
Huygens
Which statement is equivalent to Newton's first law?
If no net force acts on an object, the motion of the object does not change.
Which of these is most directly related to the mass of an object?
Inertia
What is "universal" about Newton's law of universal gravitation?
It applies to any two objects at any location.
Which of the following is true regarding speed?
It is described in terms of meters and seconds.
How is the equilibrant related to the net force?
It is equal in magnitude and opposite in direction.
A 0.40 kg block rests on a desk. The coefficient of static friction is 0.20. You push the side of the block but do not have a spring scale to measure the force you use. The block does not move. Which statement is true about the force of static friction?
It is no larger than 0.78 N.
A 0.80 kg block rests on a desk. The coefficient of static friction is 0.40. You push the side of the block but do not have a spring scale to measure the force you use. Which statement is true about the force of static friction?
It is no larger than 3.1 N.
Why is the x- y- Cartesian coordinate system important to the motion of an object in two dimensions?
It is used as a frame of reference.
Which of the following features makes the metric system easy to use?
It uses a decimal system of measurements.
The force of gravity on the moon is one-sixth that on earth. What would happen if you dropped your pen on the moon?
It would fall at one-sixth the rate of acceleration on earth.
When an object that has been thrown into the air reaches its maximum height, which is true?
Its velocity is zero.
Which of the following is a derived unit that expresses energy?
Joule
Which of the following is a unit of energy?
Joule
What should you do in the intermediate steps of a numerical calculation?
Keep at least a couple of extra digits beyond those needed for determining significant figures.
The expression "Every action has an equal but opposite reaction" is often used in everyday speech. A local government may pass a law that is unpopular, which is the action, and some citizens later react by trying to get the law repealed. Which of the following shows why this set of actions differ from Newton's third law in physics?
The action and reaction do not occur at the same instant of time.
If you plotted vector arrows around a mass to represent gravitational field vectors, describe how the length of the arrows would change as the locations at which they are drawn become closer to the mass that produces the field.
The arrows would become longer.
If you plotted vector arrows at selected points around a mass to represent the gravitational field vectors, how should the arrows change as the points for which they are drawn become more distant from the mass that produces the field?
The arrows would become shorter.
You need to estimate the floor area of your unusual oval-shaped living room from memory. You remember that it is longer than it is wider, and is about 6 m long. So you take it to be rectangular with a width of 0.5 m and multiply width by length to get an estimate of 3 m^2 . Why was your estimate not done correctly?
The assumed width was unrealistic.
What is gravitation?
The attraction of any two objects because of their mass.
A bowling ball leaves a bowler's hand. An accelerometer inside the ball reads zero. Which of the following best describes what happens to the ball?
The ball moves at a constant speed.
A bicycle and rider travel along a road. Which of the following statements is true?
The bicycle and the rider undergo translation.
A bicyclist is riding north on level ground and has zero net force. A single force pointing south then acts on the bicycle. What effect does the new force have on the motion of the bicycle?
The bicycle slows down.
Suppose you are in a rowboat that is calmly drifting on a lake on a warm summer day. You happen to have a large rock on board. You throw it out of the back of the boat as hard as you can. What happens as a result?
The boat moves forward.
Which of the observations listed is the best evidence supporting Einstein's conception of gravity?
The detection of black holes.
The vector A is a force, and the vector R is the result of adding a second force vector to it. What must be true of the vector, added to A, that gives R as the resultant?
The direction of the vector is up and to the right.
Suppose an astronaut throws a ball on the moon. What will be different for the ball thrown on the moon compared to a ball thrown the same way on earth?
The distance it travels before falling to the ground.
A dart from a small dart gun is fired straight up. As it rises, it slows down, and then it falls. Assume air resistance has no effect. Which of the following statements is true about this situation?
The downward force on the dart does not change.
Which part of this graph is chart junk?
The dramatic background picture that beautifies the graph.
A braking car on dry pavement has a constant acceleration of −6.0 m/s^2. Skid marks created are 33.3 m long. The driver claims that he was going 36 km/h. Which of the following statements is true?
The driver was lying because he was traveling at least 72 km/h.
A 60.0 kg student is standing on the pavement outside. To use Newton's law of universal gravitation to find the weight of the student, you should calculate the weight as the force of attraction between the student and what?
The entire earth, located one earth radius away.
Which of the following can you determine from the graph of the force of the sun on a comet?
The force increases as the distance decreases.
What does it mean for a force to act in accordance with an inverse square law?
The force is directly proportional to 1/r^2 where r is the distance.
Which of these would you include in a free body diagram of a coin balanced on its edge on a table?
The force of gravity acting on the coin.
Which of these discoveries is generally attributed to Newton?
The force of gravity acts between any two objects.
Which of these should a free body diagram of a car being driven along a highway include?
The force of gravity on the car.
Which of these does Newton's law of universal gravitation imply?
The force of the earth's gravity on an object at sea level is stronger than at the top of a mountain.
What does a free body diagram always illustrate?
The forces acting on an object.
Which principle was unknown in the time of Copernicus but later made it possible to explain a mechanism by which the earth orbits the sun?
The gravity of the sun attracts the earth.
Why would scientists perform an order-of-magnitude calculation of the number of stars in the universe, rather than calculating them exactly?
The information needed for an exact calculation is unknown.
For the velocity-time graph shown, which statement describes what happens to the velocity between approximately 11 s and 15 s?
The lander's velocity decreases toward the reference.
In the graph, why is the velocity positive at time 0.0 s?
The mass is moving upward and at the origin at 0.0 s.
The distance vs. time graph of a car moving at constant speed should be a straight line. Why do the data points in the graph plotted from observing the motion not fall right on the line?
The measurements are inexact.
Which of these is correct about the moon's motion around the earth?
The moon is in free fall.
A passenger on a balloon drops a baseball over the side of the gondola. As the baseball falls faster in the + direction, the drag force from air resistance increases. How does this affect the net force on the ball?
The net force decreases.
From a starting point, walk five steps. Then after making a right-angle (90°) turn, walk four steps. Which of the following most closely approximates how far you are from the starting point without regard for the path you took?
You are about six steps away from your original position.
Suppose you are on a team in a tug-of-war. You are pushing your feet into the ground, and the ground is pushing back on you. The rope is also pulling you. The result of all your effort is that you are holding your position and not moving. What is the net force acting on you?
Zero
Suppose you are seated motionless in a chair. What is the net force acting on you?
Zero
Which of the following best describes an object at constant velocity?
a = 0
Suppose you are using a system of units based on the centimeter (cm) for length, the gram (g) for mass, and the second (s) for time. The kinetic energy that an object has because of its motion is equal to half its mass times its speed squared, or KE = 1/2 mv^2 . In this system of units, what units would be used to express KE?
g times cm^2/s^2
If you divide force (kg⋅m/s^2) by acceleration (m/s^2) what units do you get?
kg
Which is the unit of the newton (N) expressed in SI base units?
kg times m/s^2
Which of the following shows the correct equivalent units of a newton in terms of SI base units?
kg times m/s^2
Which of the following is the correct description of a joule in terms of SI base units?
kg times m^2/s^2
Which of these units results when a distance of 35 m is multiplied by a force of 27 N, and then divided by a time of 5 s? A newton (N) is kg⋅m/s^2 in SI base units.
kg times m^2/s^2
Work, measured in joules, is force × distance. If the unit of force is kg⋅m/s^2, then which of the following is the correct description of joule in terms of SI base units?
kg times m^2/s^2
Which of the following is a derived unit that expresses speed?
m/s
Which of these calculations could you use to find momentum if momentum is equal to mass times velocity and velocity is equal to displacement divided by time?
mass times displacement/time
The force of gravity between any two ordinary objects on the earth is __________.
stronger if the objects are more massive
Which of the following best describes an object at rest relative to a reference point?
v = 0, a = 0.
Which equation represents inverse proportionality?
y = m/x
Which equation represents direct proportionality?
y = mx
