A ball of mass 0.4 kg is initially at rest on the ground. It is
kicked and leaves the kicker's foot with a speed of 5.0 m/s A student conducts an experiment in which an object
in a direction 60° above the horizontal. The magnitude of travels across a horizontal surface while for 2s a net force
the impulse imparted by the ball to the foot is most nearly is applied to a 2 kg object that initially travels with a speed
- ANSWER -2 N*s of 0.5 m/s. Data collected from the experiment are used to
create the graph of the magnitude of the applied force
exerted on the object as a function of time is shown. All
A force of constant magnitude F and fixed direction acts frictional forces are considered to be negligible. Can the
on an object of mass m that is initially at rest. If the force student use the graph and the known data to determine
acts for a time interval ∆t over a displacement ∆x , what is the momentum of the object after the force has been
the magnitude of the resultant change in the linear applied? - ANSWER -No, because the student needs
momentum of the object? - ANSWER -FΔt to know the direction that the force is applied to the object
because the applied force will be in the same direction as
the change in momentum of the object.
A person applies an impulse of 5.0 kg∙m/s to a box in
order to set it in motion. If the person is in contact with the
box for 0.25 s, what is the average force exerted by the Cart A with a mass of 2.0 kg travels at a constant speed of
person on the box? - ANSWER -20.0N 3.0 m/s to the right on a horizontal surface, as shown in
the figure. Cart A then collides with cart B with a mass of
1.5 kg that is initially at rest... - ANSWER -Equation 1
An object of known mass M with speed vo travels toward and Equation 2
a wall. The object collides with it and bounces away from
the wall in the opposite direction in which the object was
initially traveling. The wall exerts an average force Fo on An object of mass 2 kg collides with an object of mass 1
the object during the collision. A student must use the kg that is at rest, as shown in the figure. A graph of the
equation \Delta p=F\Delta tΔp=FΔt to determine the force as a function of time that the 1 kg object exerts on
change in momentum of the object from immediately the 2 kg object is shown. - ANSWER -(2 kg) (2m/s-
before the collision to immediately after the collision. v0)=1/2(8000 N)(0.00125 s)
Which side of the equation could the student use to
determine the change of the object's momentum? -
ANSWER -Neither side of the equation may be used How does an air mattress protect a stunt person landing
because there are too many unknown quantities before, on the ground after a stunt? - ANSWER -It lengthens
during, and after the collision. the stopping time of the stunt person and reduces the
force applied during the landing.
In an experiment, an object is released from rest near and
above Earth's surface. A student must determine the Ball X of mass 1.0 kg and ball Y of mass .5 kg travel
relationship between the direction of the gravitational toward each other on a horizontal surface... -
force exerted on the object and the change in momentum ANSWER -ball Y will travel at a speed greater
caused by that force. What data could the student collect
to determine the magnitude and direction of the
gravitational force and the change in momentum of the Assume that the collision in each scenario is elastic. A
object? Justify your choices. Select two answers. - graph of the magnitude of the force exerted on Cart Y as a
ANSWER -The mass of the object, because it is function of time for scenario 1 is shown. During which
required to determine the force due to gravity exerted on interval of time does the magnitude of the momentum of
the object, and the velocity of the object the instant before Cart Y change the most? - ANSWER -.004s to .006s
it reaches Earth's surface, because it is required to
determine the change in velocity of the object.
A student drops an object from rest above a force plate
The mass of the object, because it is required to that records information about the force exerted on the
determine the force due to gravity exerted on the object, object as a function of time during the time interval in
and the distance fallen by the object, because the force is which the object is in contact with the force plate. Which of
exerted during the entire falling distance. the following measurements should the student take, in
addition to the measurements from the force plate, to
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, Physics MCQ Test Questions with Complete Solutions
determine the change in momentum of the object from student...
immediately before the collision to immediately after the
collision? - ANSWER -The student has enough
information to make the determination. An object of mass 5kg travels in the positive direction with
a speed of 1m/s. The object collides with a second object
that exerts an average net force over an interval of time
The student conducts a second experiment in which the such that the 5kg object comes to rest. Which of the
magnitude of the force exerted on block X from block Y is following best predicts the change in momentum for the
measured over the time in which the collision takes place. 5kg object? - ANSWER -in the negative direction
A graph of the force as a function of time is shown. In a
third experiment, the student creates a collision such that
the force exerted on block X from block Y is constant for A student conducts three experiments in which a cart of
0.020 s. Which of the following constant forces, if exerted mass M is pushed along a horizontal surface of negligible
on block X from block Y, would produce the same change friction for 20s by an applied force. The graph shows the
in momentum as is shown by the graph? - force as a function of time for each experiment. Which of
ANSWER -200N the following correctly ranks the greatest change in the
cart's momentum from 0s to 20s? - ANSWER -=,=
A student must determine a nonzero change in
momentum of an object for a specific interval of time. A ball is released from rest above a horizontal surface.
Which of the following experiments could the student The ball falls downward and collides with the surface with
conduct? Select two answers. - ANSWER -drop a a speed of 2.0m/s. The average force exerted during the
ball and give a block collision is 20N over a time interval of 0.1s. Which of the
following best predicts what will happen to the ball
immediately after the collision? - ANSWER -The ball
A student must conduct an experiment in which a block is will come to rest on the surface
pulled across a horizontal surface by a spring scale so
that a nonzero change in momentum of the block can be
determined for a specific time interval. The student also Two model cars, A and B, have the same mass but
has access to measuring tools that are found in a typical different bumpers. The acceleration of each car during its
physics laboratory. Which of the following experiments collision with a wall is measured, and the data are shown
could the student conduct to determine the change in in the graphs above. Which of the following statements
momentum of the cart? Select two answers. - about the collisions are correct? Select two answers. -
ANSWER -Attach the spring scale to the block, and ANSWER -The cars, the change
pull the block so that its speed increases as it travels
across the horizontal surface. Record the force that the
spring scale exerts on the block. Use a stopwatch to A student obtains data on the magnitude of force applied
determine the time that the block is in motion. to an object as a function of time and displays the data on
the graph above.
Attach the spring scale to the block, and pull the block so
that its speed increases as it travels across the horizontal Answer the following question for the information and
surface. Use the motion detector to record the speed of diagram above.
the block at the beginning of the time interval and at the
end of the time interval. Use a mass balance to measure The increase in the momentum of the object between t = 0
the mass of the block. s and t = 4 s is most nearly - ANSWER -60 N*s
An object is used in three different experiments so that a A spacecraft of mass 4000 kg is traveling in a straight line
student can analyze the motion of the object when a net in the positive direction. Engines can be fired so that the
force is exerted on it. The data obtained from the three force exerted on the spacecraft is in the positive or
experiments are shown in the table. How can the student negative direction. The graph above shows data for the
use the data to determine the relationship between the force during one interval. Which of the following is the best
object's change in momentum and the direction of the net estimate of the net change in the speed of the spacecraft
force exerted on the object? - ANSWER -The from time t = 0 to time t = 4 s? - ANSWER -+.1m/s
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