Physics Final

A rock is thrown straight down with an initial velocity of 14.5 m/s from a cliff. What is the rock's displacement after 2.0 s? (Acceleration due to gravity is 9.80 m/s2.)

49 m

A stone is thrown horizontally from the top of a cliff. One second after it has left your hand, its vertical distance below the cliff is about

5 m

What is the mass of 5.2 L of water?

5.2 kg

Rupel pushes a box 3.00 m by applying a 19.0-N horizontal force. What work does she do?

57 J

The acceleration due to gravity on the Moon's surface is one-sixth that on Earth. An astronaut's life support backpack weighs 350 lb on Earth. What does it weigh on the Moon?

58 lb

A train slowly climbs a 450-m mountain track which is at an angle of 10.0° with respect to the horizontal. How much altitude does it gain?

78.1

Which of the following expresses a principle, which was initially stated by Galileo and was later incorporated into Newton's laws of motion?

The natural condition for a moving object is to remain in motion.

_______________ is represented by a number and units. The units are always a distance unit cubed.

Volume

When we add a displacement vector to another displacement vector, the result is:

another displacement.

Objects that are either at rest or moving with constant velocity

are in equilibrium.

As a projectile moves in its parabolic path, the velocity and acceleration vectors are perpendicular to each other

at the peak of its path

The standard metric unit for measuring Kinetic Energy is the

joule

The standard metric unit for measuring gravitational Potential Energy is the

joule

The standard metric unit for mass is the ___________.

kilogram

Which of the following is that form of energy associated with an object's motion?

kinetic

In mechanics, physicists use three basic quantities to derive additional quantities. Mass is one of the three quantities. What are the other two?

length and time

The acceleration of a freely falling object will be ________ on top of a mountain compared to what it would be sea level.

less

According to the scientific definition of work, pushing on a rock accomplishes no work unless there is

movement in the same direction as the direction of the force.

The unit of work, joule, is dimensionally the same as:

newton-meter.

The work done by static friction can be:

positive. negative. zero.

rm of energy associated with an object's location in a conservative force field?

potential

The rate at which work is done is equivalent to which of the following?

power

A rock is thrown upward at 50° with respect to the horizontal. As it rises, its horizontal component of velocity

remains unchanged.

Vector points north, and vector points east. If = − , then vector points:

south of east.

A quantity of 15 m/s is a measure of

speed

A Geo Metro and an 18-wheeler collide. Which experiences the greater acceleration?

the Metro

A strobe photograph shows equally spaced images of a car moving along a straight road. If the time intervals between images is constant, which of the following cannot be positive?

the acceleration of the car

Since 1983 the standard meter has been defined in terms of which of the following?

the distance light travels in a certain fraction of a second

As you commute to work or school in the morning, which is most likely the larger?

the distance you travel

The statement by Newton that "for every action there is an opposite but equal reaction" is regarded as which of his laws of motion?

third

An object is raised above the ground, gaining a certain amount of potential energy. If the same object is raised twice as high it gains

twice as much potential energy.

Displacement is which of the following types of quantities?

vector

Which type of quantity is characterized by both magnitude and direction?

vector

Which of the following is an example of a vector quantity?

velocity

Which quantity has the greatest influence on the amount of kinetic energy that a large truck has while moving along a highway?

velocity

The quantity of work equal to one joule is also equivalent to which of the following?

watt ⋅ s

When an object is moved to a different elevation, like up on a mountain, its _____________ changes.

weight

A change in a physical quantity w having initial value wi and final value wf is given by which of the following?

wf − wi

What is the "net force" on a car traveling along at constant speed in a straight line?

zero

Which one of the choices below represents the preferred practice regarding significant figures when adding the following: ?

​85

How many significant figures does the number 1700 have?

​One cannot tell with certainty when the number is written in the given form, but it will be one of the other given answers.

An object moves 20 m east in 20 s and then returns to its starting point taking an additional 50 s. If east is chosen as the positive direction, what is the sign associated with the average velocity of the object?

0 (no sign)

An object moves 20 m east in 20 s and then returns to its starting point taking an additional 60 s. If west is chosen as the positive direction, what is the average speed of the object?

0.5 m/s

A 9.0-kg bowling ball experiences a net force of 6.0 N. What will be its acceleration?

0.67 m/s2

Which of the following is biggest?

1 m3

A taxicab moves five blocks due north, six blocks due east, and another three blocks due north. Assume all blocks are of equal size. What is the magnitude of the taxi's displacement, start to finish?

10 blocks

A push on a 1kg brick accelerates the brick. Neglecting friction, to equally accelerate a 10kg brick, one would have to push with

10 times the force.

A 50-g ball traveling at 24.0 m/s is bounced off a brick wall and rebounds at 19.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 4.00 ms, what is the average acceleration of the ball during this time interval?

10,750 m/s2

How many centimeters are in a meter?

100

A rock, released at rest from the top of a tower, hits the ground after 1.5 s. What is the speed of the rock as it hits the ground? (g = 9.8 m/s2 and air resistance is negligible)

15 m/s

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s. What is the speed after the first 5.00 s of acceleration? (Hint: First convert the speed to m/s.)

17.4 m/s

When three vectors are added graphically and form a closed triangle, the largest enclosed angle between any two of the vectors cannot be greater than:

180°.

What is the kinetic energy of a 0.155-kg baseball thrown at 50.0 m/s (112 mph)?

193.75 J

The number 0.00017 has how many significant figures?

2

Yuri, a Russian weightlifter, is able to lift 265 kg 2.20 m in 2.10 s. What is his power output?

2.72 kW

A student adds two vectors with magnitudes of 230 and 40. Which one of the following is the only possible choice for the magnitude of the resultant?

230

Gwen releases a rock at rest from the top of a 39-m tower. If g = 9.8 m/s2 and air resistance is negligible, what is the speed of the rock as it hits the ground?

28 m/s

Assume when using a meter stick measuring can be done so that the last significant figure is the millimeter digit. If you are measuring an object with length between 25 and 26 cm, how many significant figures will result?

3

A European sports car dealer claims that his car will accelerate at a constant rate from rest to 100 km/hr in 9.00 s. If so, what is the acceleration? (Hint: First convert speed to m/s.)

3.09 m/s2

When NASA was communicating with astronauts on the moon, the time from sending on the Earth to receiving on the moon was 1.28 s. Find the distance from Earth to the moon. (The speed of radio waves is 3.00 × 108 m/s.)

384 000 km

The length and width of a standard sheet of paper is measured, and then the area is found by calculation to be 91.50 in2. The number of significant figures in the width measurement must be at least:

4

A car moves twice as fast as another identical car. Compared to the slower car, the faster car has

4 times the KE.

A rock is thrown straight up with an initial velocity of 22.54 m/s. What time interval elapses between the rock's being thrown and its return to the original launch point? (Acceleration due to gravity is 9.80 m/s2.)

4.60 s

Doubling the radius of a sphere results in increasing its volume by a factor of

8

A vehicle designed to operate on a drag strip accelerates from zero to 28 m/s while undergoing a straight line path displacement of 48 m. What is the vehicle's acceleration if its value may be assumed to be constant?

8 m/s2

A cart is given an initial velocity of 7.0 m/s and experiences a constant acceleration of 2.5 m/s2. What is the magnitude of the cart's displacement during the first 6.0 s of its motion?

87 m

A drag racer starts from rest and accelerates at 11 m/s2 for the entire distance of 400 m. What is the velocity of the race car at the end of the run?

94 m/s

____________ can be represented by a number and units. The units are always a distance unit squared.

Area

A car rounding a curve at a constant speed is not undergoing any sort of acceleration.

False

Note the expression: y = x2. Which statement is most consistent with this expression?

If x doubles, then y quadruples.

The metric standard unit for measuring work is the

Joule

Areas have dimensions ____ while volumes have dimensions ____.

L2, L3

"When a net external force acts on an object, the acceleration that results is directly proportional to the net force and inversely proportional to the mass" is a description of

Law of Acceleration

"An object continues in a state of rest or in a state of motion at a constant speed along a straight line, unless compelled to change that state by a net force" is a description of

Law of Inertia

When an object is dropped from a tower, what is the effect of the air resistance as it falls?

None of the above choices are valid.

A hiker walks 200 m west and then walks 100 m north. In what direction is her resulting displacement?

None of the answers is correct.

None of the above choices are valid.

a measure of the work that was required to put the book on the shelf from the floor. equal to the weight of the book times the distance above the floor. equal to the energy the book has because of its position above the floor

Acceleration is

a vector quantity.

How long has it been that scientists have accepted that the nucleus of the atom consists of neutrons and protons? Think of your answers in terms of order of magnitude.

about a century

A quantity of 15 m/s2 is a measure of

acceleration

A baseball is thrown by the center fielder (from shoulder level) to home plate where it is caught (on the fly at shoulder level) by the catcher. At what point is the magnitude of the acceleration at a minimum? (air resistance is negligible)

acceleration is constant during entire trajectory

In the absence of air resistance

all objects fall and accelerate at the same rate.

A baseball is thrown by the center fielder (from shoulder level) to home plate where it is caught (on the fly at shoulder level) by the catcher. At what point does the magnitude of the vertical component of velocity have its minimum value? (air resistance is negligible)

at the top of the trajectory

ball is thrown by the center fielder (from shoulder level) to home plate where it is caught (on the fly at an equal shoulder level) by the catcher. At what point is the ball's speed at a minimum? (air resistance is negligible)

at the top of the trajectory

If we know that a nonzero net force is acting on an object, which of the following must we assume regarding the object's condition? The object is:

being accelerated.

A Geo Metro and an 18-wheeler collide. Which experiences the greater force?

both experience the same amount of force

Acceleration occurs when an object

changes speed and/or direction.

Since 1967 the standard definition for the second has been based on which of the following?

characteristic frequency of the cesium-133 atom

In a 2-dimensional Cartesian coordinate system the x-component of a given vector is equal to that vector's magnitude multiplied by which trigonometric function, with respect to the angle between vector and x-axis?

cosine

In a 2-dimensional Cartesian coordinate system the y-component of a given vector is equal to that vector's magnitude multiplied by which trigonometric function, with respect to the angle between vector and y-axis?

cosine

As an object is lowered into a deep hole in the surface of the earth, which of the following must be assumed in regard to its potential energy?

decrease

A rock is thrown upward at 50° with respect to the horizontal. As it rises, its vertical component of velocity

decreases.

An object is propelled along a straight line path by a force. If the net force were doubled, its acceleration would

double.

A "push or a pull" describes

force

Which of the following is an example of a nonconservative force?

friction

tof the type of force that acts at a distance?

gravitational magnetic electrical

"Mass" tells us

how much stuff is in an object the quantity of matter in an object the measure of inertia

What condition must apply to a system's state of motion for it to be regarded as an inertial frame of reference?

in constant velocity

The horizontal component of a projectile's velocity

is constant.

If we know an object is moving at constant velocity, we may assume:

the net force acting on the object is zero.