Physics MCQ key Study Guide Exam
And Actual Answers.
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 in a direction 60° above the horizontal. The magnitude of the impulse
imparted by the ball to the foot is most nearly - Answer 2 N*s
A force of constant magnitude F and fixed direction acts on an object of mass m that is initially
at rest. If the force acts for a time interval ∆t over a displacement ∆x , what is the magnitude of
the resultant change in the linear momentum of the object? - Answer FΔt
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 person on the box? -
Answer 20.0N
An object of known mass M with speed vo travels toward 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 the object during the collision. A student must use the
equation \Delta p=F\Delta tΔp=FΔt to determine the change in momentum of the object from
immediately before the collision to immediately after the collision. 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 because there are too many unknown quantities before,
during, and after the collision.
In an experiment, an object is released from rest near and above Earth's surface. A student
must determine the relationship between the direction of the gravitational force exerted on the
object and the change in momentum 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 object? Justify your choices. Select two answers. - Answer The mass of the
object, because it is required to determine the force due to gravity exerted on the object, and
the velocity of the object the instant before it reaches Earth's surface, because it is required to
determine the change in velocity of the object.
The mass of the object, because it is required to determine the force due to gravity exerted on
the object, and the distance fallen by the object, because the force is exerted during the entire
falling distance.
A student conducts an experiment in which an object travels across a horizontal surface while
, 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.
Cart A with a mass of 2.0 kg travels at a constant speed of 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 and Equation 2
An object of mass 2 kg collides with an object of mass 1 kg that is at rest, as shown in the figure.
A graph of the force as a function of time that the 1 kg object exerts on the 2 kg object is shown.
- Answer (2 kg) (2m/s-v0)=1/2(8000 N)(0.00125 s)
How does an air mattress protect a stunt person landing on the ground after a stunt? - Answer
It lengthens the stopping time of the stunt person and reduces the force applied during the
landing.
Ball X of mass 1.0 kg and ball Y of mass .5 kg travel toward each other on a horizontal surface... -
Answer ball Y will travel at a speed greater
Assume that the collision in each scenario is elastic. A graph of the magnitude of the force
exerted on Cart Y as a function of time for scenario 1 is shown. During which interval of time
does the magnitude of the momentum of Cart Y change the most? - Answer .004s to .006s
A student drops an object from rest above a force plate that records information about the
force exerted on the object as a function of time during the time interval in which the object is
in contact with the force plate. Which of the following measurements should the student take,
in addition to the measurements from the force plate, to determine the change in momentum
of the object from immediately before the collision to immediately after the collision? - Answer
The student has enough information to make the determination.
The student conducts a second experiment in which the magnitude of the force exerted on
block X from block Y is measured over the time in which the collision takes place. 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 0.020 s. Which of the following
constant forces, if exerted on block X from block Y, would produce the same change in
momentum as is shown by the graph? - Answer 200N
A student must determine a nonzero change in momentum of an object for a specific interval of
time. Which of the following experiments could the student conduct? Select two answers. -
And Actual Answers.
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 in a direction 60° above the horizontal. The magnitude of the impulse
imparted by the ball to the foot is most nearly - Answer 2 N*s
A force of constant magnitude F and fixed direction acts on an object of mass m that is initially
at rest. If the force acts for a time interval ∆t over a displacement ∆x , what is the magnitude of
the resultant change in the linear momentum of the object? - Answer FΔt
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 person on the box? -
Answer 20.0N
An object of known mass M with speed vo travels toward 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 the object during the collision. A student must use the
equation \Delta p=F\Delta tΔp=FΔt to determine the change in momentum of the object from
immediately before the collision to immediately after the collision. 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 because there are too many unknown quantities before,
during, and after the collision.
In an experiment, an object is released from rest near and above Earth's surface. A student
must determine the relationship between the direction of the gravitational force exerted on the
object and the change in momentum 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 object? Justify your choices. Select two answers. - Answer The mass of the
object, because it is required to determine the force due to gravity exerted on the object, and
the velocity of the object the instant before it reaches Earth's surface, because it is required to
determine the change in velocity of the object.
The mass of the object, because it is required to determine the force due to gravity exerted on
the object, and the distance fallen by the object, because the force is exerted during the entire
falling distance.
A student conducts an experiment in which an object travels across a horizontal surface while
, 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.
Cart A with a mass of 2.0 kg travels at a constant speed of 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 and Equation 2
An object of mass 2 kg collides with an object of mass 1 kg that is at rest, as shown in the figure.
A graph of the force as a function of time that the 1 kg object exerts on the 2 kg object is shown.
- Answer (2 kg) (2m/s-v0)=1/2(8000 N)(0.00125 s)
How does an air mattress protect a stunt person landing on the ground after a stunt? - Answer
It lengthens the stopping time of the stunt person and reduces the force applied during the
landing.
Ball X of mass 1.0 kg and ball Y of mass .5 kg travel toward each other on a horizontal surface... -
Answer ball Y will travel at a speed greater
Assume that the collision in each scenario is elastic. A graph of the magnitude of the force
exerted on Cart Y as a function of time for scenario 1 is shown. During which interval of time
does the magnitude of the momentum of Cart Y change the most? - Answer .004s to .006s
A student drops an object from rest above a force plate that records information about the
force exerted on the object as a function of time during the time interval in which the object is
in contact with the force plate. Which of the following measurements should the student take,
in addition to the measurements from the force plate, to determine the change in momentum
of the object from immediately before the collision to immediately after the collision? - Answer
The student has enough information to make the determination.
The student conducts a second experiment in which the magnitude of the force exerted on
block X from block Y is measured over the time in which the collision takes place. 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 0.020 s. Which of the following
constant forces, if exerted on block X from block Y, would produce the same change in
momentum as is shown by the graph? - Answer 200N
A student must determine a nonzero change in momentum of an object for a specific interval of
time. Which of the following experiments could the student conduct? Select two answers. -
