Name: ________________________ Class: ___________________ Date: __________
ID: A
Exam 2--PHYS 101--Fall 2014
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1. Consider these vectors. What is A-B?
a.
b.
a
b
c.
d.
c
d
2. Consider these two vectors. What is the magnitude
of their sum?
3. Which of these are vector quantities?
I. mass
II. distance
III. velocity
IV. acceleration
a. I
b. III & IV
c. I & III
d. II, III, & IV
e. all of these
ä
A = 10.0 units at 30.0 degrees above the -x-axis
ä
B = 10.0 units along the -x-axis
(Note the angle for both is measured from the
negative x axis.)
a.
b.
c.
d.
4. A cannonball is fired horizontally at 10 m/s from a
cliff. Its speed one second after being fired is about
10.7 units
19.3 units
17.0 units
22.0 units
a.
b.
c.
d.
1
16 m/s
10 m/s
14 m/s
20 m/s
Name: ________________________
ID: A
8. A large cannon is fired from ground level over
level ground at an angle of 30° above the
horizontal. The muzzle speed is 1000 m/s.
Neglecting air resistance, the projectile will travel
what horizontal distance before striking the
ground?
5. A vector in the xy plane has a magnitude of 25m
and an x component of 12m. The angle it
makes with the positive x axis is:
a.
b.
c.
d.
e.
26°
241°
61°
64°
29°
6. A bullet shot horizontally from a gun:
a. travels in a straight line
b. strikes the ground much sooner than one
dropped from the same point at the same
instant
c. strikes the ground much later than one dropped
vertically from the same point at the same
instant
d. strikes the ground at approximately the same
time as one dropped vertically from the same
point at the same instant
e. never strikes the ground
a.
b.
c.
d.
e.
170 km
4.3 km
43 km
87 km
8.5 km
9. Which of these plots represents the y-component of
the velocity for an object launched from the ground
at an angle and returns to the same y-position?
7. A stone is thrown horizontally from the top of a
125-m high cliff with a velocity of 10.0m/s . How
far does the stone land from the base of the cliff?
a.
b.
c.
d.
e.
a.
b.
c.
d.
e.
10 m
50 m
5m
100 m
200 m
a
b
c
d
none of these
10. Given that A + B = C, and that |A|2 + |B|2 =|C|2, how
are vectors A and B oriented with respect to each
other?
a. separated by some unknown angle
b. perpendicular
c. parallel and in same direction
d. separated by 30 degrees
e. antiparallel (parallel but in opposite directions)
2
Name: ________________________
ID: A
14. A 10.0 kilogram stone is initially at rest and
accelerated by a force of 15.0 newtons. After 6.0
seconds, what is the stone’s velocity?
11. This figure shows the path a projectile takes when
fired at an angle of 0 degrees. The dashed lines
show the distance from the level of the cannon to
where the projectile has fallen. The projectile
travels for equal amounts of time, t, between each
dashed line. If the distance M is 2 meters, what are
the distances N and O?
a.
b.
c.
d.
a.
b.
c.
d.
15. You run out of gas. You and your friends have to
push your car out of the road. Which of these
statements best explain why it is difficult to move
the car?
a. the car has a big weight
b. the car has a lot of mass
c. the car experiences a very large frictional force
d. you and your friends are very weak
N=4 m; O=8 m
N=8 m; O=32 m
N=2 m; O=4 m
N=8 m; O=18 m
12. A cart is being pulled along a horizontal track by
an external force and accelerating. A cannon on
the cart fires straight upwards. After it is fired,
what happens to the ball?
a.
b.
c.
d.
16. A karate chop delivers a force of 3000 N to a board
that breaks. The force that the board exerts on the
hand during this event is
a.
b.
c.
d.
the cannonball falls into the cart
the cannonball falls behind the cart
it depends on the initial velocity of the
cannonball
the cannonball falls in front of the cart
less than 3000 N
3000 N
greater than 3000 N
need more information
17. Consider a block that is at rest on an inclined plane.
The only forces acting on the block are the
frictional, normal, and gravitational forces. Which
of these statements best describe the normal force
acting on the block?
a. N>mg
b. N<mg
c. N=mg
d. it depends on the weight of the block
13. Which of these projectiles remains in the air for the
longest amount of time?
a.
b.
c.
d.
9.0 m/s
40 m/s
900 m/s
25 m/s
a
b
c
it depends on their initial velocity
3
Name: ________________________
ID: A
20. A block of mass 10 kg sits at rest on a horizontal
surface. A force of 20 N is applied at 30 degrees
from the x-axis. What is the normal force acting on
the block?
18. You push on a mass with a certain force, and the
mass accelerates at 1 m/s 2. With the same force,
you push on a second mass. The acceleration of
the second mass is 3 m/s2. Now, you stick the 2
masses together and push on them with the same
force. What is the acceleration of the 2 masses?
a.
b.
c.
d.
2m
s2
1 m
2
s2
3 m
2
s2
3 m
4
s2
a.
b.
c.
d.
19. A block of 10 kg is on an inclined plane as shown
here. A rope is attached to the block and goes over
a frictionless pully; a force of 100 N is applied to
the rope. What is the rate of acceleration for the
block?
21. For the previous problem, the coefficient of kinetic
friction between the block and surface is 0.1. At
what rate does the block accelerate to the right?
a.
b.
c.
d.
a.
b.
c.
d.
e.
80 N
90 N
10 N
100 N
0 m/s2
1.3 m/s2 up the inclined plane
3.2 m/s2 up the inclined plane
2.0 m/s2 down the inclined plane
5.0 m/s2 up the inclined plane
4
2.1 m/s2
0.8 m/s2
1.2 m/s2
1.7 m/s2
Name: ________________________
ID: A
25. The normal force on an object is always:
a. equal to the gravitational force
b. abnormally large
c. in the upward direction
d. perpendicular to the surface on which the
object sits
e. opposite the direction of the object’s motion
22. We step on the accelerator of our Subaru providing
a force F on the car for a time of 10 seconds and
speeding it up to a final speed of 60 miles/hour. If
1
the applied force were 2 F, what would be the final
speed after 20
seconds?
26. Which of these statements about the coefficients of
friction is true?
a.
b.
c.
d.
a.
90 miles/hour
30 miles/hour
120 miles/hour
60 miles/hour
b.
c.
27. You apply a force in the x-direction of 20 N on a
block that has a mass of 10 kg. If no other forces
act on the block, what is its acceleration?
a. 2 m/s2
b. 200 m/s2
c. 0.5m/s2
d. 5 m/s2
23. A cart is on a horizontal frictionless table. Once
the cart has been pushed and released, what will
happen to it?
a.
b.
c.
d.
it will immediately come to a stop
it will continue at constant velocity
it will continue at constant acceleration
it will gradually slow down
24. An elevator goes downward at a constant
acceleration. What is the relationship between the
weight of the object (W) and the normal force on
the block (N)?
a.
b.
c.
d.
µs > µk
µs < µk
µs = µk
W>N
W=N
W<N
not enough information
5
ID: A
Exam 2--PHYS 101--Fall 2014
Answer Section
MULTIPLE CHOICE
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