Download AP Physics Laws of Motion MC Sample Test

AP Physics
Laws of Motion
MC Sample Test
1.
Which of these is true about mass?
I. It is the amount of matter an object consists of.
II. It is an objects weight.
III. Inertia is a consequence of having mass.
IV. It changes with the strength of gravity g.
(A) I only.
(B) II only.
(C) I and II.
(D) I and III.
(E) All of these are true for mass.
7.
An object initially at rest moves a distance x when a force
F is applied for a time t. How far will the object move if
a force of 2F is applied for the same time t ?
2
(A)
x
2
2x
(B)
(C) 2x
(D) 2 2x
(E) 4x
2.
The tendency of objects to maintain their velocity is
caused by
(A) force and stated in Newton’s 1st Law.
(B) force and stated in Newton’s 2nd Law.
(C) inertia and stated in Newton’s 2nd Law.
(D) mass and stated in Newton’s 1st Law.
(E) impedus and stated in Newton’s 1st Law.
8.
A 10 kg mass is accelerated upward by a rope at 2 m/s2.
The tension in the rope is
(A) 50 N.
(B) 80 N.
(C) 100 N.
(D) 120 N.
(E) 200 N.
3.
Starting a vehicle moving from rest on a horizontal surface
on the moon requires
(A) the same forward force.
(B) less forward force, since mass on the moon is
smaller.
(C) less forward force, since weight on the moon is
smaller.
(D) more forward force, due to the absence of an
atmosphere.
(E) Requires more information to answer.
9.
The space shuttle increases its acceleration every second
during take off, even though its engines generate the same
amount of force. Which off these contributes the most
significantly to this effect?
(A) Gravity g is decreasing.
(B) It is losing mass as it burns fuel.
(C) The air gets thinner at higher altitudes.
(D) Acceleration increases since the engines have burned
for a longer period of time.
4.
Two different objects have the same density and both
weigh 100 N. However, one is on a planet where gravity is
greater than on earth. Which object is larger?
(A) Mass of a single object does not change from planet
to planet.
(B) The object on Earth is larger.
(C) The object on the other planet is larger.
(D) The scales read incorrectly due to the gravity change,
and both objects are the same size.
(E) Not enough information to say.
5.
Which is true regarding an objects weight?
I. It is the same everywhere regardless of gravity.
II. It is a scalar, while mass is a vector.
III. It is the force acting on mass in a gravity field.
IV. It is the same as mass. The force of gravity is g.
(A) I only.
(B) II only.
(C) III only.
(D) IV only.
(E) I and IV.
6.
In balanced force problems, which can be determined
conclusively?
(A) the object is at rest.
(B) the object is at constant nonzero velocity.
(C) there is a net force acting on the object.
(D) the sum of force vectors is zero.
(E) None of the above.
10. When an object is thrown upward, in the absence of air
resistance, and reaches the top of its trajectory it stops
instantaneously. At this point the net force acting on the
object is
(A) g
(B) zero.
(C) the objects weight.
(D) the objects mass.
(E) changing directions
11. Two objects with different masses are dropped from the
same height with no air resistance. They reach the ground
at the same time because
(A) mass is not a factor and thus has no effect on
acceleration.
(B) the more massive object has more inertia and requires
more force to accelerate at the same rate.
(C) the same net force acts on both objects, creating the
same acceleration.
(D) weight is not a factor in acceleration of dropped
objects.
(E) This does not happen. The heavier object strikes the
ground first.
12. A small object with a weight of 50 N is experiencing the
gravitational force of the entire Earth. The object pulls
back on the Earth with a force of
(A) 0 N.
(B) Non zero force, but small enough to be negligible.
(C) 5 N.
(D) 50 N.
(E) 500 N.
13. In a tug of war both sides of the rope are pulled with a
force of 500 N. Then tension in the rope is
(A) 0 N.
(B) 50 N.
(C) 250 N.
(D) 500 N.
(E) 1000 N.
16. A 70 kg person stands on a scale in an elevator that is
accelerating upward at 2 m/s2. What does the scale report?
(A) 560 N.
(B) 700 N.
(C) 840 N.
(D) 960 N.
(E) 1000 N.
14. A rocket moves upward during its launch. Which of these
is true?
(A) Exhaust gases push on the Earth creating an equal
and opposite upward force.
(B) Exhaust gases push on air molecules creating an
equal and opposite upward force.
(C) Exhaust gases pushed backwards by the rocket are
the action force, and the rocket moving in the
opposite direction is the reaction force.
(D) The force of the exhaust gases must be small so that
they don’t add too much downward force to gravity.
If they do the rocket will not have enough upward
force.
(E) All of these are incorrect.
17. A 70 kg person stands on a scale in an elevator that is
moving at constant downward velocity of 2 m/s. What
does the scale report?
(A) 560 N.
(B) 700 N.
(C) 840 N.
(D) 960 N.
(E) 1000 N.
15. When you push on an object the reaction force depends on
(A) the object’s mass.
(B) your mass.
(C) the objects speed.
(D) your speed.
(E) None of these.
18. When an object hangs at static equilibrium from two ropes,
which of the following is true in every possible case?
(A) Each rope supports the objects weight.
(B) The tension in the two ropes adds to the objects total
weight.
(C) The vertical components of each ropes tension
support half the objects weight.
(D) The vertical components of tension add together to
equal the objects weight.
(E) Each of these covers a special case, but none covers
every possible problem of this type.
1.
D
7.
C
13. D
2.
D
8.
D
14. C
3.
A
9.
B
15. E
4.
B
10. C
16. C
5.
C
11. B
17. B
6.
D
12. D
18. D