Physics A
A stone that starts at rest free falls for 7.0 s. How far does the stone fall in this time?
-2.4 x 102 m
A net force of 6.8 N accelerates a 31 kg scooter across a level parking lot. What is the magnitude of the scooter's acceleration?
0.22 m/s^2
Find the total displacement of a mouse that travels 1.0m north and then 0.8m south.
0.2m north
A stagehand starts sliding a large piece of stage scenery originally at rest by pulling it horizontally with a force of 176 N. What is the coefficient of static friction between the stage floor and the 490 N piece of scenery?
0.36
Which of the following equations is not an equation for power, P, in terms of work, W, displacement, d, time interval, 656-06-04-00-00_files/i0040000.jpgt, force, F, and/or velocity, v?
D
A student walks from the door of the house to the end of the driveway and realizes that he missed the bus. The student runs back to the house, traveling three times as fast. Which of the following is the correct expression for the return velocity if the initial velocity is vstudent?
-3vstudent
What is the angular displacement of the second hand on a clock after 59 seconds?
-6.17 rad
Your friend drops your house keys down to you from their second floor window. If you catch them 2.4 m from where your friend dropped them, what is the velocity of the keys when you catch them?
-6.9 m/s
A painter accidentally drops a can of paint from a high scaffold. How far has the can fallen after 4.0 s?
-78 m
A ball with a momentum of 4.0 kg·m/s hits a wall and bounces straight back without losing any kinetic energy. What is the change in the ball's momentum?
-8.0 kg·m/s
The drum of a clothes dryer turns at 635 rev/min. If the door to the dryer is opened, the motor is turned off. If the drum requires 8.0 s to slow to a stop, what is the angular acceleration of the drum?
-8.3 rad/s2
A single force acts on an object. The components of this force act along the +x-axis and the -y-axis. The single force that will bring the object into equilibrium has components that act along the
-x-axis and +y-axis.
A worker does 25 J of work lifting a bucket, then sets the bucket back down in the same place. What is the total net work done on the bucket?
0 J
What is the speed of an object at rest?
0.0 m/s
Earth exerts a 1.0 N gravitational force on an apple. What is the magnitude of the gravitational force the apple exerts on Earth?
1
Basking in the sun, a 1.10 kg lizard lies on a flat rock tilted at an angle of 15.0° with respect to the horizontal. What is the magnitude of the normal force exerted by the rock on the lizard?
10.4 N
A waitperson carrying a tray with a platter on it tips the tray at an angle of 12° below the horizontal. If the gravitational force on the platter is 5.0 N, what is the magnitude of the force parallel to the tray that tends to cause the platter to slide down the tray? (Disregard friction.)
1.0 N
A car is moving with a uniform speed of 15.0 m/s along a straight path. What is the distance covered by the car in 12.0 minutes?
1.08 ´ 10^1 km
A piano that weighs 575 N is lifted 20.0 m straight up by a rope attached to a motor-driven winch. It takes 10.0 s for the piano to reach this height. What power is developed by the motor in kW?
1.15 kW
Carrie has a mass of 43 kg and sits 1.8 m from the center of a seesaw. Steve wants to balance Carrie. If Steve has a mass of 52 kg, how far from the center of the seesaw should he sit?
1.5 m
A 61.5 kg student sits at a desk 1.25 m away from a 70.0 kg student. What is the magnitude of the gravitational force between the two students? (G = 6.673 ´
1.84 x 10^-7 N
Two boxes are on opposite ends of a plank that is 3.0 m long. The plank is supported in the middle by a fulcrum. The box on the left has a mass, m1, of 25 kg. The box on the right has a mass, m2, of 15 kg. Use the formulas below to determine how far the fulcrum must be positioned from the right side of the plank in order to balance the masses horizontally. (Hint: g=9.8m/s2)
1.9 m
Which of the following is a pair of vector quantities?
Velocity — Displacement
Using the position-time graph of the bowling ball shown above, how far did the ball travel between 0.0 s and 5.0s?
10 m
What is the volume of a cube whose side is 10 m? (Volume = length x width x height)
1000 m3
What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s?
108 J
Estimate the order of magnitude of the length of a football field.
10^2 m
What do giga and femto mean?
10^9, 10^-15
A change in the gravitational force acting on an object will affect the object's
weight.
A comet experiences uniform acceleration from 60 m/s to 183 m/s in 10.0 s. What is its rate of acceleration?
12.3 m/s2
The magnitude of the gravitational force acting on an object is
weight.
According to the position-time graph shown, what is the biker's displacement at time t=3.0s?
15.0 m
Two perpendicular forces, one of 45.0 N directed upward and the other of 60.0 N directed to the right, act simultaneously on an object with a mass of 35.0 kg. What is the magnitude of the resultant acceleration of the object?
2.14 m/s^2
A fish swims 12.0 m in 5.0 s. It swims the first 4.0 m in 2.0 s, the next 3.0 m in 1.2 s, and the last 5.0 m in 1.8 s. What is the average velocity of the fish during the time interval between 0.0 s and 3.2 s?
2.2 m/s
Suppose a certain type of deciduous tree releases 8500 leaves on average each fall. If the average mass of each leaf is 1.3 g and a 148,000 acre forest has 198 of these trees per acre, how many kilograms of leaves are dropped per acre each fall?
2.2 x 10^3 kg/acre
A 5.0 kg hoop rotates about a perpendicular axis through its center. A force of 25 N is exerted tangentially to the hoop. If the hoop has a radius is 2.0 m, what is its angular acceleration?
2.5 rad/s2
A washing machine has a fast spin cycle of 542 rev/min and a slow spin cycle of 328 rev/min. The diameter of the washing machine drum is 0.43 m. What is the ratio of the centripetal accelerations for the spin cycles? Recall that ac = v2/r and v= rw.
2.73
How much elastic potential energy is stored in a bungee cord with a spring constant of 10.0 N/m when the cord is stretched 2.00 m?
20.0 J
A horizontal force of 200 N is applied to move a 55 kg television set across a 10 m level surface. What is the work done by the 200 N force on the television set?
2000 J
It takes you 5 min to walk with an average velocity of .75 m/s to the north from the parking lot to the entrance of the amusement park. What is your displacement?
225 m to the north
A box has a length of 12 cm, a height of 22 cm, and a width of 18 cm. How tall would a stack of 12 of these boxes be?
264 cm
Sara runs several times a week and always keeps track of how much time she runs each time she goes out. One day she forgets to take her stopwatch with her and wonders if she can still have some idea of her running time. As she passes a particular pond, she remembers that it is 5.6 km from her house. She knows from her previous training that she has a consistent pace of 3.4 m/s. How long has Sara been running when she reaches the pond?
27.5 minutes
What forces act on the cars of a roller coaster when they enters loops and turns after reaching the initial summit?
All of the above.
A runner maintains a constant velocity of +3.0 m/s. Which of the following position-time graphs shows the runner's location from the starting point at 5.0 s intervals for 30.0 s?
B
The temperature drops from 48 Celsius to 21 Celsius in 9 hours. Find the average temperature change per hour.
3 Celsius/hour
One runner in a relay race has a 1.50 s lead and is running at a constant speed of 3.25 m/s. The runner has 30.0 m to run before reaching the end of the track. A second runner moves in the same direction as the leader. What constant speed must the second runner maintain in order to catch up to the leader at the end of the race?
3.9 m/s
A 1.0 m-long lever is attached to a rotating rod that is perpendicular to the lever. By pushing down on the end of the lever with a force of 60 N, you can rotate the rod. If the force on the lever is exerted at a 30º angle, what torque is exerted on the lever? (sin 30º = 0.5; cos 30º = 0.87, tan 30º = 0.58)
30 N•m
The length of a room is 15.2 m, its width is 4.9 m, and its height is 4.1 m. What volume does the room enclose?
305.4 m3
A train travels from Albuquerque, New Mexico, to Mexico City in 4 hours with an average velocity of 80 km/h to the south. What is the train's displacement?
320 km to the south
Sam must perform a job that requires a torque of 32.4 N·m. He must use a 0.234-m-long wrench and exert a force of 232 N. What is the smallest angle, with respect to the vertical, that Sam needs to exert this amount of force?
36.6º
How much power is required to lift a 2.0 kg mass at a speed of 2.0 m/s?
39 W
If the displacement of a horizontal mass-spring system was doubled, the elastic potential energy in the system would change by a factor of
4.
The gravitational force between two masses is 36 N. What is the gravitational force if the distance between them is tripled? (G = 6.673
4.0 N
Two of the tires on a tractor-trailer have 1.5 m diameters. If the tractor-trailer travels at a linear velocity of 3.0 m/s, what is the angular velocity of each tire?
4.0 rad/s
If a is acceleration align='absmiddle'v is change in velocity (m/s), align='absmiddle'x is change in position (m), and align='absmiddle't is the time interval (s), which equation is not dimensionally correct?
C
Two small masses that are 10.0 cm apart attract each other with a force of 10.0 N. When they are 5.0 cm apart, these masses will attract each other with what force?
40.0 N
In the free-body diagram shown above, which of the following is the gravitational force acting on the balloon?
4050 N
A string is wrapped around a cylinder and pulled with force of 13.0 N. The cylinder's radius is 0.150 m. The cylinder's rotational speed goes from 0.0 to 14.0 rev/min in 4.50 s. What is the moment of inertia of the cylinder?
5.99 kg·m2
The length of a rectangular plot of land is 151.28 m, and its width is 72.35 m. What is the perimeter of this plot?
447.3 m
A cyclist maintains a constant velocity of +7.0 m/s. At time t=0.0 s, the cyclist is +150 m from point A.The cyclist is moving away from point A. What is the cyclist's position from point A at 45.0 s?
465 m
50 g of ice at 0°C is dropped in a beaker containing 100 g of water at 0°C. What will be the contents of the beaker after 5 hours? Assume that the room temperature is 0°C.
50 g of ice and 100 g of water
A gear spins at 1880 rev/min. What is the angular displacement of the gear in 2.50s?
492 rad
How many significant figures does 0.050200 mg have?
5
There are six books in a stack, and each book weighs 5 N. The coefficient of static friction between the books is 0.2. With what horizontal force must one push to start sliding the top five books off the bottom one?
5 N
Water flows over the edge of a waterfall at a rate of 1.2 x 106 kg/s. There are 50.0 m between the top and bottom of the waterfall. How much power is generated by the falling water by the time it reaches bottom?
5.9 x 108 W
The time required to make a trip of 100.0 km is measured at various speeds. From the graph above, what speed will allow the trip to be made in 2 hours?
50.0 km/h
A water tank has a mass of 2.43 kg when it is empty, and a mass of 54.2 kg when it is filled to a certain level. What is the mass of the water contained in the tank at this level?
51.8 kg
What is the average power supplied by a 60.0 kg person running up a flight of stairs a vertical distance of 4.0 m in 4.2 s?
560 W
A child pulls a balloon for 12 m with a force of 1.0 N at an angle 60° below horizontal. How much work does the child do on the balloon?
6.0 J
Which of the following equations best describes the graph above?
D
A planet has a mass of 5.68 x 1026 kg and a radius of 6.03 x 107 m. What is the weight of a 65.0 kg person on the surface of this planet?
678 N
For the winter, a duck flies 10.0 m/s due south against a gust of wind with a speed of 2.5 m/s. What is the resultant velocity of the duck?
7.5 m/s south
Which of the following equations expresses Newton's law of universal gravitation?
D
A late traveler rushes to catch a plane, pulling a suitcase with a force directed 30.0° above the horizontal. If the horizontal component of the force on the suitcase is 60.6 N, what is the force exerted on the handle?
70.0 N
Which of the following equations expresses the work-kinetic energy theorem?
D
Two trucks with equal mass are attracted to each other with a gravitational force of 6.7 ´ N. The trucks are separated by a distance of 3.0 m. What is the mass of one of the trucks? (G = 6.673
9.5 x 10^3kg
A solid wooden wheel accelerates at 3.25 rad/s2 when a force of 4.5 N exerts a torque on it. If this wheel is replaced by a wheel with all of its mass on the rim, the moment of inertia is given by I = mr2. If the same angular velocity were desired, what force would have to be exerted on the wheel?
9.0 N
A sled weighing 1.0 x 10^2 N is held in place on a frictionless 20.0° slope by a rope attached to a stake at the top. The rope is parallel to the slope. What is the normal force of the slope acting on the sled?
94 N
It takes 15 minutes to walk to the mall from your house at an average velocity of 1.1 m/s to the east. What is the displacement from your house to the mall?
990 m to the east
5000 J of heat is supplied in one minute to 0.06 kg of a liquid at its boiling point of 85°C to convert it completely to vapor. Which of the following expressions gives the heat of vaporization of the liquid?
A
Which of the following situations is an example of a visible change in momentum?
A baseball is hit by a bat.
Which situation shows unbalanced forces acting on an object?
A book sitting still and then sliding on a table top.
What apparatus was used by Cavendish to discover the universal gravitation constant (G)?
A rigid rod suspended by a wire which was 6-feet long to which two small metal spheres were attached to the ends.
If a force is exerted on an object, which statement is true?
A small force applied over a long time interval can produce a large change in the object's momentum.
Which of the following situations is an example of a significant change in momentum?
A tennis ball is hit into a net.
Which of the following is the equation for acceleration?
B
__________ is predicted by dividing the net force by the mass of the object.
Acceleration
How can a position-time graph show if an object has constant acceleration?
By showing distance over time
What forces act on the cars of a roller coaster when they enters loops and turns after reaching the initial summit?
All of the above
Which of the following is a correct interpretation of the expression
All of the above are correct interpretations.
What is true about mechanical energy?
An object with mechanical energy can exert an applied force on another object.
If you are able to see an object, how can you be sure that it is not at absolute zero?
As soon as light hits the object, it gives the object energy and it will no longer be at absolute zero
Which of the following statements are TRUE when the spaces on a ticker-tape diagram do not change?
Both A and B.
Why do scientists use the metric system?
Both A and B.
What can a skydiver do to increase air resistance and slow themselves down?
Both b and c.
Bus A and Bus B leave school on a field trip when a stopwatch reads zero. Bus A travels at a constant 50 km/h, and Bus B travels at a constant 75 km/h. How far are the two buses from school when the stopwatch reads 1.5 h?
Bus A is 75 km from school, Bus B is 112.5 km from school
Odina walked down the hall at school from the cafeteria to the band room, a distance of 100.0m. A class of physics students recorded and graphed her position every 2.0s, noting that she moved 2.6m every 2.0s. Which of the following graphs represents Odina's motion?
C
The graph above describes the motion of a ball. At what point does the ball have an instantaneous velocity of zero?
C
The mass of Mars is kg, and the mass of a single proton is kg. Assuming Mars is made entirely of protons, how many protons would make up Mars?
C
To melt 4 kg of a solid, 106 J of heat is required. Which of the following expressions gives the heat of fusion of the solid?
C
What is the SI unit of acceleration?
C
Which of the following statements about centrifugal force is true?
Centripetal acceleration gives rise to the illusion of centrifugal force.
In the steps of the scientific method, what is the next step after formulating a hypothesis?
Conducting Experiments
Four sheep are traveling the 250 m distance from the pasture back to the barn. After 45 seconds, their distances from the barn are as follows: Dolly - 170 m, Fluffy - 115 m, Ellie - 90 m, Ma - 200 m. According to average velocity, how would the sheep rank from fastest to slowest?
Ellie, Fluffy, Dolly, Ma
A bolt is to be tightened with a torque of 8.0 N·m. If you have a wrench that is 0.35 m long, you must exert at least 33 N of force to tighten the bolt.
F
A hard drive on a modern computer spins at 7200 rpm (revolutions per minute). If the drive is designed to start from rest and reach operating speed in 1.5 s, then the angular acceleration of the disk must be 2.0 x 103 rad/s2.
F
According to the First Law of Thermodynamics, the change in thermal energy of an object is equal to the heat added to the object divided by the work done by the object.
F
In the sentence, "A student works on a term paper," the scientific meaning of work is intended.
F
It is more important to be precise with measurements than accurate.
F
The temperature of a system must increase when heat energy is added.
F
You replace the tires on your car with tires that have a larger diameter. After you change the tires, for trips at the same speed and over the same distance, the angular velocity and number of revolutions will both increase.
F
A student attaches a rope to a couch with a mass of 50 kg. She pulls with a force of 70 N at an angle of 45° with the horizontal force. The coefficient of kinetic friction between the couch and the sidewalk is 0.500. Find the frictional force.
FK= 220.5
A free-body diagram only includes the gravitational force acting on an object.
False
A volleyball is dropped from a cliff and a soccer ball is thrown upward from the same position. When each ball reaches the ground at the bottom of the cliff, the volleyball will hit the ground with greater velocity.
False
According to the graph shown, the total distance traveled during the recorded time interval was 5.0 m.
False
In a motion diagram, the size of the object must be less than the distance moved.
False
Internal motions within the object are used in creating a particle model.
False
Mass is the magnitude of the force due to gravity acting on an object.
False
Motion diagrams are used to show the location of a non-moving object over specific time intervals.
False
Quantities must have different units before they can be added or subtracted.
False
The number of significant digits in the mass of a body measuring 4200.0 kg is 2.
False
Which of the following statements does not describe force?
Force causes objects at rest to remain stationary.
In the figure above, which diagram represents the vector addition C = A + B?
II
In the figure above, which diagram represents the vector subtraction C = A-B?
IV
Why is an object sitting on a table at equilibrium?
It is not accelerating
What is true of the velocity versus time graph of an object receiving an applied net force?
It will be a line with either a positive or a negative slope.
Why doesn't the principle of mechanical energy conservation hold in situations when frictional forces are present?
Kinetic energy is not completely converted to a form of potential energy.
The following students measure the density of a piece of lead three times. The density of lead is actually 8.9 g/cm3. Considering all of the results, which person's results are both accurate and precise?
Lila: 8.89 g/cm3, 8.91 g/cm3, 8.92 g/cm3
The most appropriate SI unit for measuring the length of an automobile is the
Meter
What are the units for a spring constant?
N/m
Which of the following equations describes the relationship between work, power, and time?
P=W/t
How might the accuracy of a measurement be checked?
Repeat using a different method
In which of the following sentences is work used in the everyday sense of the word?
Sam and Rachel worked hard pushing the car.
How fast an object is moving
Speed
A 1.80 m ladder rests on two supports. Support A is 0.60 m from one end of the ladder, while support B is 0.15 m from the other end of the ladder. Which of the following statements about the forces acting on the ladder is true?
Support A exerts a greater force.
A motion diagram will tell the change in position of an object over a specific time interval.
T
A stunt driver maneuvers a sportscar so that it is traveling on only two wheels. The center of mass of the car is directly above the line between the points where the two wheels are touching the ground.
T
According to the Second Law of Thermodynamics, natural processes go in a direction that increases the total entropy in the universe.
T
Particle models use a designated point to represent motion of an object over specific time intervals.
T
Precision is the degree of exactness or refinement of a measurement. Accuracy is the extent to which a reported measurement approaches the standard or accepted value of the quantity measured.
T
The acceleration of an object is not zero at the top of its flight, because the acceleration of gravity on the object does not change.
T
The center of mass of a car tire is in the middle of the tire.
T
The direction of a normal force is perpendicular to the surface the object is sitting on.
T
The entropy of a system measures the state of disorder of the system.
T
The entropy of an isolated system never decreases.
T
The temperature of a bottle containing water rises when it is shaken vigorously since shaking adds heat to the system
T
The two SI units for work are newton-meters (N·m) and joules (J).
T
Which statement about the acceleration of an object is correct?
The acceleration of an object is directly proportional to the net external force acting on the object and inversely proportional to the mass of the object.
What does the graph above illustrate about acceleration?
The acceleration varies.
A wooden beam that is 6.50 m long weighs 325 N. It rests on two supports that are 3.00 m apart, with equal amounts of the beam extending from each end. Sarah, who weighs 575 N, stands on the beam in the center and then walks toward one end. What will happen to the beam as Sarah moves toward the end?
The beam will tip over and fall as equilibrium is disrupted.
When a car's velocity is positive and its acceleration is negative, what is happening to the car's motion?
The car slows down.
A child with a mass of 23 kg rides a bike with a mass of 5.5 kg at a velocity of 4.5 m/s to the south. Compare the momentum of the child with the momentum of the bike.
The child has a greater momentum than the bike.
Why does an astronaut weigh less on the moon than on Earth?
The gravitational field strength is less on the moon's surface than on Earth's surface.
Why isn't there a change in temperature during a phase change?
The energy would be used by the increasing motion of molecules
A 4.5-m-long wooden board with a 24-kg mass is supported in two places. One support is directly under the center of the board, and the other is at one end. What can be said about the forces exerted by the supports?
The force exerted by the center support is greater than the force exerted by the end support.
Gravitational Force
The force that caused objects to be attracted to each other, and that depends on mass and distance between the objects
A hammer drives a nail into a piece of wood. Identify an action-reaction pair in this situation.
The hammer exerts a force on the nail; the nail exerts a force on the hammer.
If friction is the only force acting on an object during a given physical process, which of the following assumptions can be made in regard to the object's kinetic energy?
The kinetic energy decreases.
A ski jumper has 1.2 ´ 10656-06-03-00-00_files/i0140000.jpg J of potential energy at the top of the ski jump. The friction on the jump slope is small, but not negligible. What can you conclude about the ski jumper's kinetic energy at the bottom of the jump?
The kinetic energy will be less than 1.2 x 104J.
When comparing the momentum of two moving objects, which of the following is correct?
The less massive object will have less momentum if the velocities are the same.
What conditions must be met for an object to be at equilibrium?
The net force and net torque must both equal zero.
If a scientist gets poor precision from the same instrument that their lab partner uses with excellent precision, what is the likely problem?
The scientist has poor technique.
Which of the following is a true statement about the conservation of energy?
Total energy is always conserved.
A time interval is a scalar quantity.
True
According to the graph shown, the bicycle's average speed and average velocity are both 0.67 km/min.
True
An object's location and the time it takes to move to that location are the two observations used to create a motion diagram.
True
In a chosen coordinate system, the position of an object in motion can have negative values.
True
The method of treating the units as algebraic quantities that can be cancelled is called dimensional analysis.
True
The position-time graph of an object moving with a constant average velocity is always a straight line.
True
The valid digits in a measurement are called significant digits.
True
Value that is measured by the slope of a position-time graph
Velocity
Which of the following equations expresses the work-kinetic energy theorem?
W=KE
Which of the following has the greatest power output?
a crane that lifts a 2.5 ´4 N beam at a speed of 1.2 m/s
A free-body diagram of a ball falling in the presence of air resistance would show
a downward arrow to represent the force due to gravity and an upward arrow to represent the force of air resistance.
The __________ is a point that lies along a vertical line drawn from the suspension point of an object when the object is at a standstill.
center of mass
When using Mx10^n to express a number using scientific notation, M is a _________, and n must be a ______.
a real number between 1 and 10, a whole number positive or negative
Which of the following line segments on a position versus time graph is physically impossible?
a vertical line
Gravitational potential energy is always measured in relation to
a zero level.
An object is _____ on a velocity versus time graph when the line moves away from the x-axis, and is _________ when the line moves closer to the x-axis.
accelerating, decelerating
____________ tells how much an object's ________ is changing.
acceleration, velocity
The friction created to slow down an object that is falling
air resistance
If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you predict?
all of the above
Power is calculated by which of the following equations?
all of the above
Which of the following can be used to depict changes in the position of an object over time?
all of the above
The angular displacement of an object divided by the time needed to make the displacement.
angualr velocity
The number of complete revolutions around a circle in one second
angular frequency
Is equal to moment of inertia multiplied by angular velocity
angular momentum
Motion can be depicted using a:
any of the above
A baseball catcher throws a ball vertically upward and catches it in the same spot as it returns to the mitt. At what point in the ball's path does it experience zero velocity and nonzero acceleration at the same time?
at the top of its path
If a nonzero net force is acting on an object, then the object is definitely
being accelerated.
Which could a scientist do to increase the precision of his data collection?
change the tool he is using to measure his data
Which of the following effects does force have on an object?
both a and b
The equation for determining gravitational potential energy is PE656-06-02-00-00_files/i0130000.jpg = mgh. Which factor(s) in this equation is (are) not intrinsic to an object?
both g and h
The equation for determining gravitational potential energy is PEg = mgh. Which factor(s) in this equation is (are) not intrinsic to an object?
both g and h
Which of the following forces arises from direct physical contact between two objects?
contact force
A truck travels 420 m. Each tire on the truck has a diameter of 42 cm. If one revolution of a tire is equal to 2π times the radius of the tire (in meters), which of the following equations shows how many revolutions each tire makes as the distance is traveled?
d
A truck travels 420 m. Each tire on the truck has a diameter of 42 cm. If one revolution of a tire is equal to 2π times the radius of the tire (in meters), which of the following equations shows how many revolutions each tire makes as the distance is traveled?
d.
When dots on a ticker-tape diagram become closer together moving left to right, the object is _________.
decelerating
Imagine a figure skater performing a spin. What will happen to angular velocity as the skater's leg is extended?
decrease
A weather balloon records the temperature every hour. From the table above, the temperature
decreases.
The Greek letter (delta) indicates a(n)
difference or change.
Tides are caused by
differences in the gravitational force of the moon at different points on Earth.
A pendulum is raised 1.5 cm and allowed to fall. If air resistance is negligible, how high will the pendulum rise on the other side?
exactly 1.5 cm
When dots are further apart on a ticker-tape diagram, it indicates an object is moving ______.
fast
Objects that are falling toward Earth in free fall move
faster and faster.
What is a force that does not involve physical contact between two objects?
field force
The newton is the SI unit of what physical quantity?
force
Which of the following is the cause of an acceleration?
force
A free-body diagram represents all of the following except
forces exerted by the object.
When calculating the gravitational force between two extended bodies, you should measure the distance
from the center of each body.
A fluid that does not have a definite volume is a __________.
gas
Calculated by the equation PEg = mgh
gravitational potential energy
Which form of energy is involved in weighing fruit on a spring scale?
gravitational potential energy and elastic potential energy
The energy needed to change a substance from one state to another is called __________ of fusion/vaporization.
heat
Which of the following is the tendency of an object to maintain its state of motion?
inertia
An object's tendency to resist acceleration is measured by the object's
inertial mass.
A force does work on an object if a component of the force
is parallel to the displacement of the object.
A lack of precision in scientific measurements typically arises from
limitations of the measuring instrument.
Movement that occurs along a straight line is called:
linear movement
The length of the force vector is proportional to what property of a force?
magnitude
The length of a force vector represents the
magnitude of the force.
What is the expression for net force? Net force =
mass x acceleration
Conservation of ____________ energy is only valid when it occurs in a situation with no frictional force.
mechanical
Which of the following refers to the sum of kinetic energy and all forms of potential energy?
mechanical energy
Which of the following are examples of conservable quantities?
mechanical energy and mass
The impulse experienced by a body is equivalent to the body's change in
momentum.
In the graph above, what is the correct description of any location to the left of the zero?
negative position
Determined through the use of resultant vectors
net external force
The sum of all forces acting on an object
net external force
The amount of force equal to 1 kg·m/s2 defines what SI unit?
newton
A crate is released on a frictionless plank inclined at angle q with respect to the horizontal. Which of the following relationships is true? (Assume that the x-axis is parallel to the surface of the incline.)
none of the above
The graph above describes the motion of a ball. At what point is the velocity of the ball equal to its velocity at B?
none of the above
In the presence of frictional force,
nonmechanical energy is no longer negligible and mechanical energy is no longer conserved.
If an object is slowing down, its acceleration is in the ___________ direction of its motion, and if it is speeding up, its acceleration is in the _________ direction.
opposite, same
Which of the following equations can be used to directly calculate an object's momentum, p?
p = mv
Three values were obtained for the mass of a metal bar: 8.83 g; 8.84 g; 8.82 g. The known mass is 10.68 g. The values are
precise.
The sum of two vectors
resultant vector
Which of the following is a physical quantity that has a magnitude but no direction?
scalar
Identify the following quantities as scalar or vector: the mass of an object, the number of leaves on a tree, wind velocity.
scalar, scalar, vector
Identify the following quantities as scalar or vector: the speed of a snail, the time it takes to run a mile, the free-fall acceleration.
scalar, scalar, vector
If velocity and time are positive in the positive y and x directions of the xy coordinate plane respectively, a velocity versus time graph for an object in free fall is a _______ line with a _______ slope.
straight, negative
If the sign of work is negative,
the displacement is in the direction opposite the force.
The free-body diagram shown above represents a car being pulled backwards by a towing cable. In the diagram, the 5800 N force is
the force exerted by the towing cable on the car.
If you lift an apple from the ground to some point above the ground, the gravitational potential energy in the system increases. This potential energy is stored in
the gravitational field between Earth and the apple.
According to Newton's second law, when the same force is applied to two objects of different masses,
the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration.
Acceleration is defined as
the rate of change of velocity.
A more powerful motor can do
the same work in a shorter time interval.
Total energy of the molecules in a substance or object
thermal energy
The statement by Newton that for every action there is an equal but opposite reaction is which of his laws of motion?
third
Newton's third law of motion involves the interactions of
two objects and two forces.
Which of the following is a physical quantity that has both magnitude and direction?
vector
Which of the following is an example of a vector quantity?
velocity
Which of the following line segments on a velocity versus time graph is physically impossible?
vertical line
The motion of a ball on an inclined plane is described by the equation Which of the following quantities must have a value of zero?
vi
A football player runs in one direction to catch a pass, then turns and runs twice as fast in the opposite direction toward the goal line. Which of the following is a correct expression for the original velocity and the resulting velocity?
vplayer, -2vplayer
A person sitting in a chair with wheels stands up, causing the chair to roll backward across the floor. The momentum of the chair
was zero while stationary and increased when the person stood.
Is equal to mass multiplied by gravitational field strength
weight
The product of the component of a force along the direction of displacement and the magnitude of the displacement are known as:
work
In the graph above, a toy car rolls from +3 m to +5 m. Which of the following statements is true?
xi = +3 m
A car goes forward along a level road at constant velocity. The additional force needed to bring the car into equilibrium is
zero
For an object to be in equilibrium, the net force acting on the object must have what value?
zero
In general, Fnet equals
ΣF.