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Version 001 – second semester final practice – gleue – (315192)
This print-out should have 75 questions.
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Holt SF 04Rev 12
001 (part 1 of 2) 10.0 points
A dog pulls on a pillow with a force of 4.5 N
at an angle of 36.2◦ above the horizontal
a) What is the x component of this force?
Correct answer: 3.63132 N.
002 (part 2 of 2) 10.0 points
b) What is the y component of this force?
force on the ball?
Correct answer: 111.278 N.
005 (part 2 of 2) 10.0 points
b) What is the direction of the resultant force
(measured from East)?
Correct answer: 33.1189◦ .
Hewitt CP9 02 E21
006 10.0 points
A hockey puck slides across the ice at a constant speed.
Which of the following is true?
Correct answer: 2.65773 N.
1. None of these
Tennis Ball
003 10.0 points
Despite a very strong wind, a tennis player
manages to hit a tennis ball with her racquet
so that the ball passes over the net and lands
in her opponent’s court.
Consider the following forces:
1. A downward force of gravity,
2. A force by the hit, and
3. A force exerted by the air.
Which of the above forces is (are) acting on
the tennis ball after it has left contact with
the racquet and before it touches the ground?
2. The puck is at rest.
1. 1, 2, and 3.
2. 1 and 2.
3. 2 and 3.
4. 1 and 3. correct
5. 1 only.
Force on a Soccer Ball
004 (part 1 of 2) 10.0 points
Sue and Jenny kick a soccer ball at exactly
the same time. Sue’s foot exerts a force of
60.8 N to the north. Jenny’s foot exerts a
force of 93.2 N to the east.
a) What is the magnitude of the resultant
1
3. The puck is moving and thus not in equilibrium.
4. The puck can be considered neither at
rest nor in equilibrium.
5. It is in equilibrium. correct
Holt SF 04A 01 graph
007 (part 1 of 2) 10.0 points
A man is pulling on a rope with a force of 89 N
directed at an angle of 36◦ to the horizontal.
What is the x-component of this force?
Draw the vectors to scale on a graph to determine the answer.
Your answer must be within ± 5.0%
Correct answer: 72 N.
008 (part 2 of 2) 10.0 points
What is the y-component of this force?
Your answer must be within ± 5.0%
Correct answer: 52 N.
Holt SF 04Rev 10
009 (part 1 of 2) 10.0 points
Four forces act on a hot-air balloon, as shown
from the side.
Version 001 – second semester final practice – gleue – (315192)
734 N
2
Force Comparison 02
012 10.0 points
416 N
261 N
282 N
Consider a person standing in an elevator
that is accelerating downward. The person
of mass m has two forces acting upon him:
the downward force m g due to gravity and
the upward supporting force n exerted by the
floor of the elevator.
~a
~n
m~g
Find the magnitude of the resultant force
on the balloon.
Which force has the largest magnitude?
Correct answer: 477.838 N.
1. n
010 (part 2 of 2) 10.0 points
Find the direction of the resultant force (measured from the 416 N force, with up positive).
2. m g correct
Correct answer: 71.0721◦.
4. If a is downward, m g = 0.
Braking Distance
011 10.0 points
A 2000 kg car experiences a constant braking
force of 10,000 N, and comes to be a stop in 6
sec.
What would be the distance traveled by the
car in coming to rest?
5. None of these
1. 60 m
2. 90 m correct
3. None of these
3. They have the same magnitude.
6. If a is downward, n = 0.
Holt SF 04Rev 50
013 10.0 points
A 4.6 kg bucket of water is raised from a well
by a rope.
The acceleration of gravity is 9.81 m/s2 .
If the upward acceleration of the bucket is
2.8 m/s2 , find the force exerted by the rope
on the bucket of water.
Correct answer: 58.006 N.
4. 180 m
5. 300 m
6. 250 m
7. 200 m
Serway CP 04 07
014 10.0 points
Then air exerts a forward force of 7 N on the
propeller of a 0.27 kg model airplane.
If the plane accelerates forward at 1.7 m/s2 ,
what is the magnitude of the resistive force
Version 001 – second semester final practice – gleue – (315192)
3
exerted by the air on the airplane?
What is the mass on the moon?
Correct answer: 6.541 N.
Correct answer: 18 kg.
Serway CP 04 11
015 (part 1 of 3) 10.0 points
A boat moves through the water with two
forces acting on it. One is a 2246 N forward
push by the motor on the propeller, and the
other is an 1946 N resistive force due to the
water around the bow.
What is the acceleration of the 1105 kg
boat?
Suspended in an Elevator
022 (part 1 of 2) 10.0 points
The tension in a string from which a 7.6 kg
object is suspended in an elevator is equal to
75 N.
What is magnitude of the acceleration a of
the elevator? The acceleration of gravity is
9.8 m/s2 .
2
Correct answer: 0.0684211 m/s2 .
Correct answer: 0.271493 m/s .
016 (part 2 of 3) 10.0 points
If it starts from rest, how far will it move in
11.2 s?
023 (part 2 of 2) 10.0 points
What is its direction?
1. upward correct
Correct answer: 17.0281 m.
2. downward
017 (part 3 of 3) 10.0 points
What will its velocity be at the end of this
time interval?
3. not moving
Correct answer: 3.04072 m/s.
Hewitt CP9 04 E15
018 (part 1 of 4) 10.0 points
1
Gravity on the surface of the moon is only
6
as strong as gravity on the Earth.
What is the weight of a 18 kg object on the
Earth? The acceleration of gravity is 10 m/s2 .
Correct answer: 180 N.
Static Equilibrium 03
024 (part 1 of 2) 10.0 points
The 7.1 N weight is in equilibrium under the
influence of the three forces acting on it. The
F1 force acts from above on the left at an
angle of 28◦ with the horizontal. The F2 force
acts from above on the right at an angle of
40◦ with the horizontal. The 7.1 N force acts
straight down.
28 ◦
F1
◦
7.1 N
019 (part 2 of 4) 10.0 points
What is the weight on the moon?
Correct answer: 30 N.
F2
40
7.1 N
020 (part 3 of 4) 10.0 points
What is the mass on the earth?
Note: F1 and F2 are not to scale.
What is the magnitude of the force F2 , as
shown in the figure above?
Correct answer: 18 kg.
Correct answer: 6.76126 N.
021 (part 4 of 4) 10.0 points
025 (part 2 of 2) 10.0 points
Version 001 – second semester final practice – gleue – (315192)
F
What is the magnitude of the force F1 , as
shown in the figure above?
F
8N
10
54 N
60◦
2.4 kg
If the surface is frictionless, what is the
magnitude of the resulting acceleration?
Correct answer: 0.659915 m/s2 .
Pushing a Lawnmower
030 10.0 points
A woman pushes a 15 kg lawnmower at a
steady speed. She exerts a 140 N force in a
direction 30◦ below the horizontal.
The acceleration of gravity is 9.8 m/2 .
14
What is the magnitude of the resulting acceleration of the block? The acceleration of
gravity is 9.8 m/s2 .
Correct answer: 0 m/s2 .
Forces on a Skier
027 (part 1 of 2) 10.0 points
A skier of mass 62.9 kg comes down a slope
of constant angle 25◦ with the horizontal.
What is the force on the skier parallel to the
slope? The acceleration of gravity is 9.8 m/s2 .
◦
61
63 kg
Correct answer: 5.86606 N.
Angled Force on a Block 01
026 10.0 points
The horizontal surface on which the block of
mass 2.4 kg slides is frictionless. The force of
54 N acts on the block in a horizontal direction
and the force of 108 N acts on the block at an
angle as shown below.
4
0N
30◦
15 kg
Find the magnitude of the vertical force
this lawnmower exerts on the lawn.
Correct answer: 217 N.
Block Sliding Down 02
031 (part 1 of 2) 10.0 points
A block starts from rest at a height of 7.1 m
on a fixed inclined plane.
Correct answer: 260.51 N.
028 (part 2 of 2) 10.0 points
What force normal to the slope is exerted by
the skis?
5. 6
kg
µ=
0. 1
8
32◦
Correct answer: 558.666 N.
Pulling a Block
029 10.0 points
~ is 28 N, the
The magnitude of the vectors F
force on the right is applied at an angle 61 ◦
and the the mass of the block is 63 kg.
What is the speed of the block at the bottom of the ramp? The acceleration of gravity
is 9.8 m/s2 . This problem requires a train of
logic:
(1) Analyze force diagram,
(2) use Newton’s Laws, and
Version 001 – second semester final practice – gleue – (315192)
(3) solve the equations of motion.
Correct answer: 9.95357 m/s.
032 (part 2 of 2) 10.0 points
If the block continues to slide on the ground
with the same coefficient of friction, how far
will the block slide on the ground until coming
to rest?
250 N
25
0N
5
31◦
18 kg
µ = 0.29
What is the magnitude of the resulting acceleration?
Correct answer: 25.0264 m/s2 .
Correct answer: 28.0821 m.
Down a Plane 02
033 (part 1 of 3) 10.0 points
A block of mass 12 kg starts from rest and
slides a distance of 9 m down an inclined
plane making an angle of 40◦ with the horizontal. The coefficient of sliding friction between
block and plane is 0.4.
The acceleration of gravity is 9.8 m/s2 .
What is the net force on the block along the
incline?
Correct answer: 39.5571 N.
034 (part 2 of 3) 10.0 points
What is the speed of the block after sliding
9 m?
Correct answer: 7.70297 m/s.
035 (part 3 of 3) 10.0 points
What would be its speed if friction were negligible?
Correct answer: 10.6484 m/s.
Forces Accelerating a Block
036 10.0 points
The magnitude of each force is 250 N, the
force on the right is applied at an angle 31 ◦
and the mass of the block is 18 kg. The
coefficient of friction is 0.29.
The acceleration of gravity is 9.8 m/s2 .
Holt SF 04C 01
037 10.0 points
Once a 28 kg crate is in motion on a horizontal
floor, a horizontal force of 51 N keeps the crate
moving with a constant velocity.
The acceleration of gravity is 9.81 m/s2 .
What is µk , the coefficient of kinetic friction, between the crate and the floor?
Correct answer: 0.185671.
Holt SF 04D 01 02
038 (part 1 of 2) 10.0 points
A student moves a box of books down the hall
by pulling on a rope attached to the box. The
student pulls with a force of 180 N at an angle
of 20.7◦ above the horizontal. The box has a
mass of 29.5 kg, and µk between the box and
the floor is 0.24.
The acceleration of gravity is 9.81 m/s2 .
Find the acceleration of the box.
Correct answer: 3.87103 m/s2 .
039 (part 2 of 2) 10.0 points
Now the student moves the box up a ramp
(with the same coefficient of friction) inclined
at 10.4◦ with the horizontal.
b) If the box starts from rest at the bottom
of the ramp and is pulled at an angle of 20.7◦
with respect to the incline and with the same
180 N force, what is the acceleration up the
ramp?
Correct answer: 2.13881 m/s2 .
Holt SF 04Rev 55
040 (part 1 of 4) 10.0 points
Version 001 – second semester final practice – gleue – (315192)
A 3.82 kg block starts from rest at the top of a
27.5◦ incline and accelerates uniformly down
the incline, moving 2.45 m in 1.24 s.
The acceleration of gravity is 9.81 m/s2 .
a) What is the magnitude of the acceleration of the block?
Correct answer: 3.18678 m/s2 .
041 (part 2 of 4) 10.0 points
b) What is the coefficient of kinetic friction
between the block and the incline?
Correct answer: 0.154336.
042 (part 3 of 4) 10.0 points
c) What is the magnitude of the frictional
force acting on the block?
Correct answer: 82.32 J.
Conceptual 08 17
047 (part 1 of 2) 10.0 points
Lora (of mass 44 kg) is an expert skier. She
starts at 2.3 m/s at the top of the lynx run,
which is 63 m above the bottom.
What is her final kinetic energy at the bottom of the ski run?
Correct answer: 27282 J.
048 (part 2 of 2) 10.0 points
What is her speed at the bottom?
Correct answer: 35.2149 m/s.
Girl on Swing 03
049 10.0 points
Correct answer: 5.13014 N.
043 (part 4 of 4) 10.0 points
d) What is the speed of the block after it slides
the distance of 2.45?
6
A girl swings on a playground swing in such
a way that at her highest point she is 2.8 m
from the ground, while at her lowest point she
is 0.5 m from the ground.
Correct answer: 3.95161 m/s.
Holt SF 05Rev 19 20
044 (part 1 of 2) 10.0 points
a) What is the kinetic energy of an automobile
with a mass of 1209 kg traveling at a speed of
12 m/s?
Correct answer: 87048 J.
045 (part 2 of 2) 10.0 points
b) What speed would a fly with a mass of
0.621 g need in order to have the same kinetic
energy as the automobile?
Correct answer: 16743.6 m/s.
Lifting a Bowling Ball
046 10.0 points
A 5.6 kg bowling ball is lifted 1.5 m into a
storage rack.
The acceleration of gravity is 9.8 m/s2 .
Calculate the increase in the ball’s potential
energy.
7.4 m
2.8 m
0.5 m
What is her maximum speed? The acceleration due to gravity is 9.8 m/s2 .
Correct answer: 6.71416 m/s.
Holt SF 06A 01
050 10.0 points
An ostrich with a mass of 160 kg is running to
the right with a velocity of 18 m/s.
Find the momentum of the ostrich.
Correct answer: 2880 kg · m/s.
Holt SF 06A 03
051 10.0 points
Version 001 – second semester final practice – gleue – (315192)
What velocity must a car with a mass of
1280 kg have in order to have the same momentum as a 2190 kg pickup truck traveling
at 29 m/s to the east?
7
m/s to the north collides with and sticks to
another railroad car of the same mass that is
moving in the same direction at 1.84 m/s.
What is the velocity of the joined cars after
the collision?
Correct answer: 49.6172 m/s.
Correct answer: 4.77 m/s.
Drag Racer 02
052 (part 1 of 2) 10.0 points
An 825 kg drag race car accelerates from rest
to 120 km/h in 0.844 s. What change in
momentum does the force produce?
Hewitt CP9 23 P02
058 10.0 points
A certain device in a 120 V circuit has a
current rating of 20 A .
Find the resistance of the device.
Correct answer: 27500 kg · m/s.
Correct answer: 6 Ω.
053 (part 2 of 2) 10.0 points
What average force is exerted on the car?
Correct answer: 32583 N.
Holt SF 06D 03
054 (part 1 of 3) 10.0 points
Each croquet ball in a set has a mass of 0.54
kg. The green ball, traveling at 11.0 m/s,
strikes the blue ball, which is at rest.
Assuming that the balls slide on a frictionless surface and all collisions are head-on, find
the final speed of the blue ball in each of the
following situations:
a) The green ball stops moving after it
strikes the blue ball.
Correct answer: 11 m/s.
Holt SF 19B 02
059 10.0 points
A stereo with a resistance of 56 Ω is connected
across a potential difference of 111 V .
What is the current in this device?
Correct answer: 1.98214 A.
Holt SF 20A 02
060 (part 1 of 3) 10.0 points
A 5.0 Ω, an 11 Ω and an 11.0 Ω resistor are
connected in series with a 12.0 V battery.
Calculate the equivalent resistance.
Correct answer: 27 Ω.
061 (part 2 of 3) 10.0 points
What is the current in the circuit?
055 (part 2 of 3) 10.0 points
b) The green ball continues moving after the
collision at 2.0 m/s in the same direction.
Correct answer: 0.444444 A.
Correct answer: 9 m/s.
062 (part 3 of 3) 10.0 points
What is the current in each resistor?
056 (part 3 of 3) 10.0 points
c) The green ball continues moving after the
collision at 0.7 m/s in the same direction.
Correct answer: 10.3 m/s.
Holt SF 06E 03
057 10.0 points
A 1.20 × 104 kg railroad car moving at 7.70
Correct answer: 0.444444 A.
Holt SF 20A 04
063 (part 1 of 4) 10.0 points
A series combination of two resistors, 9.34 Ω
and 4.90 Ω, is connected to a 6.00 V battery.
Calculate the equivalent resistance of the
circuit.
Version 001 – second semester final practice – gleue – (315192)
Correct answer: 14.24 Ω.
064 (part 2 of 4) 10.0 points
Calculate the current in the circuit.
9.0 Ω
9.0 Ω
What is its equivalent resistance?
Correct answer: 18 Ω.
Correct answer: 0.421348 A.
065 (part 3 of 4) 10.0 points
What is the potential difference across the
9.34 Ω resistor?
Correct answer: 3.93539 V.
066 (part 4 of 4) 10.0 points
What is the potential difference across the
4.90 Ω resistor?
Correct answer: 2.06461 V.
Holt SF 20B 04
067 (part 1 of 4) 10.0 points
A 19.0 Ω, 12.0 Ω, and 6.00 Ω resistor are
connected in parallel to an emf source. A
current of 7.00 A is in the 12.0 Ω resistor.
Calculate the equivalent resistance of the
circuit.
Correct answer: 3.30435 Ω.
068 (part 2 of 4) 10.0 points
What is the potential difference across the
source?
072 (part 2 of 5) 10.0 points
9.0 Ω
9.0 Ω
What is the equivalent resistance?
Correct answer: 4.5 Ω.
073 (part 3 of 5) 10.0 points
9.0 Ω
9.0 Ω
9.0 Ω
What is the equivalent resistance?
Correct answer: 3 Ω.
074 (part 4 of 5) 10.0 points
9.0 Ω
9.0 Ω
9.0 Ω
What is the equivalent resistance?
Correct answer: 84 V.
Correct answer: 6 Ω.
069 (part 3 of 4) 10.0 points
Calculate the current in the 19.0 Ω resistor.
Correct answer: 4.42105 A.
070 (part 4 of 4) 10.0 points
Calculate the current in the 6.00 Ω resistor.
Correct answer: 14 A.
Holt SF 20Rev 35
071 (part 1 of 5) 10.0 points
Consider the circuit
075 (part 5 of 5) 10.0 points
What is the equivalent resistance?
9.0 Ω
9.0 Ω
9.0 Ω
What is the equivalent resistance?
Correct answer: 13.5 Ω.
8