ame: ________________________ Class: ___________________ Date: __________
Quiz 3--PHYS 101-3T--Chapters 4b, 5, & 6
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1. A mass of 2.0 kg sits on an inclined plane as shown
here. What must the force F be for the block to
accelerate up the plane at 5.0 m/s 2?
3. What happens to the normal force acting on an
object on an inclined plane (as in the figure for the
previous problem) as the angle θ is increased?
a. FN is always constant
b. FN decreases
c. FN is dependent only on the weight
d. FN increases
4. When a car’s tires are rolling, which of these is the
type of friction between the road and tire?
a. static friction
b. kinetic friction
c. normal friction
d. all of these are relevant
5. A box of weight 100 N is at rest on a floor where
µs= 0.5. A rope is attached to the box and pulled
horizontally with tension F T = 30 N. Which way
does the box move?
a. 10 N
b. 20 N
c. 60 N
d. 40 N
e. 30 N
2. What is the normal force acting on the block in the
previous problem?
a.
b.
c.
d.
a.
b.
c.
d.
e.
Fw
F w sin(30°)
F w cos(30°)
F + F w cos(30°)
1
to the left
to the right
up
down
the box doesn’t move
ame: ________________________
6. Consider the block at rest at the top of this frictionless inclined plane. What is the block’s speed when it reaches
the bottom? (let g= 10 m/s2)
a.
b.
c.
8 m/s
10 m/s
20 m/s
d.
e.
9 m/s
60 m/s
9. A box is being pulled across a rough floor at a
constant speed. What can you say about the work
done by friction?
a. friction does no work
b. friction does positive work
c. friction does negative work
d. friction does both positive and negative work.
10. How does the work required to stretch a spring 6
cm compare with the work required to stretch it 2
cm?
a. 2 times as much work to stretch it 6 cm
b. 3 times as much work to stretch it 6 cm
c. 4 times as much work to stretch it 6 cm
d. 9 times as much work to stretch it 6 cm
e. 12 times as much work to stretch it 6 cm
7. Imagine that the inclined plane above does have
frictional forces acting on the block. If this force is
2N, what energy is lost after the block has moved
down the incline plane?
a. 10 J
b. 2 J
c. 5 J
d. 8 J
8. If the frictional force is 2N on the inclined plane
above, what kinetic energy does the block have at
the bottom of the inclined plane?
a.
b.
c.
d.
e.
310 J
290 J
20 J
10 J
300 J
2
ame: ________________________
13. A 1.0 kg block is travelling to the right at 3.0 m/s.
It collides with a stationary 2.0 kg block, and the
two blocks stick together. What is their final
velocity?
11. A guy pulls a block 5.0 m across the floor as shown
here. What work is done?
a. 1 m/s
b. 3 m/s
c. 1.5 m/s
d. 2 m/s
14. Which of these statements is true?
a. energy is a scalar quantity;
momentum is a vector
b. both energy and momentum are vector
quantities
c. energy is a vector;
momentum is scalar
d. both energy and momentum are scalar
quantities
15. Two boxes, one heavier than the other, are initially
at rest on a horizontal frictionless surface. The
same constant force F acts on each one for exactly
1 second. Which box has more momentum after
the force acts?
a. the light one
b. the heavy one
c. both the same
a. 150 J
b. 500 J
c. 130 J
d. 75 J
12. For the previous problem, what is the normal force
on the block?
a.
b.
c.
d.
e.
230 N
200 N
26 N
170 N
30 N
3
ame: ________________________
18. A 75-kg swimmer dives horizontally off a 500-kg
raft. If the diver's speed immediately after leaving
the raft is 4 m/s, what is the corresponding raft
speed?
16. Alex throws a 0.15-kg rubber ball down onto the
floor. The ball's speed just before impact is 6.5 m/s,
and just after is 3.5 m/s. What is the magnitude of
the change in the ball's momentum?
a. 4.3 kg⋅m/s
b. 126 kg⋅m/s
c. 1.5 kg⋅m/s
d. 0.09 kg⋅m/s
17. Alex throws a 0.15-kg rubber ball down onto the
floor. The ball's speed just before impact is 6.5 m/s,
and just after is 3.5 m/s. If the ball is in contact
with the floor for 0.025 s, what is the magnitude of
the average force applied by the floor on the ball?
a.
b.
c.
d.
a. 0.5 m/s
b. 4.0 m/s
c. 0.6 m/s
d. 0.2 m/s
19. In which of these collisions is momentum
conserved?
a. people colliding
b. gas particles colliding
c. cars colliding
d. all of these
20. An elastic collision is one in which
a. only momentum is conserved
b. only energy is conserved
c. both energy and momentum are conserved
d. neither energy or momentum are conserved
60 N
3.0 N
3.5 N
133 N
4
ID: A
Quiz 3--PHYS 101-3T--Chapters 4b, 5, & 6
Answer Section
MULTIPLE CHOICE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
E
B
B
A
E
A
A
B
C
D
D
D
A
A
C
C
A
C
D
C
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
DIF: 2
DIF: 2
DIF: 2
TOP: 6.1 Momentum and Impulse
TOP: 6.1 Momentum and Impulse
TOP: 6.2 Conservation of Momentum
1