Download Physics Benchmark Exam #1 2008-2009

Physics Benchmark Exam #1 2009-2010
(Formula Sheet is on Page 13)
For questions 1 and 2, the graph below represents the displacement of an object as a
function of time.
1. What is the velocity of the object at t = 1 second?
A
B
C
D
1.0 m/s
1.5 m/s
2.0 m/s
3.0 m/s
2. What is the average velocity of the object from t = 0 to t = 3 seconds?
A
B
C
D
1.0 m/s
2.0 m/s
3.0 m/s
0 m/s
3. A ball is dropped from rest from a height 6.0 meters above the ground. The ball falls
freely and reaches the ground 1.1 seconds later. What is the average speed of the ball?
A
B
C
D
5.5 m/s
6.1 m/s
6.6 m/s
11 m/s
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4. To create real-time graphs of an object’s displacement versus time and velocity versus
time, a student would need to use a:
A
B
C
D
motion sensor.
low-g accelerometer.
potential difference probe.
force probe.
5. The figure above shows a block that is being pulled along the floor. According to the
figure, what is the acceleration of the block?
A
B
C
D
2 m/s2 to the right
3 m/s2 to the left
4 m/s2 to the right
6 m/s2 to the left
6. A 50-kg child on a skateboard experiences a 75-N force as shown. What is the expected
acceleration of the child?
A
B
C
D
0.67 m/s2
1.50 m/s2
6.70 m/s2
25.00 m/s2
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7. A car is traveling at a constant speed of 14 meters per second along a straight highway.
A tree and a speed limit sign are beside the highway. As it passes the tree, the car starts
to accelerate. The car is accelerated uniformly at 2.0 meters per second2 until it reaches
the speed limit sign, 5.0 seconds later. When the car reaches the sign, the car’s speed is:
A
B
C
D
less than the speed limit.
greater than the speed limit.
equal to the speed limit.
there is not enough information to answer the question.
8. A student in a lab experiment jumps upward off a common bathroom scale as the lab
partner records the scale reading.
What does the lab partner observe during the instant the student pushes off?
A The scale reading will remain unchanged during the entire time the student is in
contact with the scale.
B The scale reading will increase momentarily then will decrease as the student is
moving upward from the scale.
C The scale reading will increase during the entire time the student is in contact
with the scale.
D The scale reading will decrease momentarily then will increase as the student is
moving upward from the scale.
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9. Equilibrium exists in a system where three forces are acting concurrently on an object.
If the system includes a 5.0-newton force due north and a 2.0-newton force due south,
the third force must be:
A
B
C
D
7.0 N south.
7.0 N north.
3.0 N south.
3.0 N north.
10. What event will produce the greatest increase in the gravitational force between the two
masses shown above?
A
B
C
D
11.
A student does an experiment to measure the acceleration of a falling object, which is
9.8 m/s2. The student obtains an experimental value of 14.6 m/s2. The reason for this
variation is most likely due to:
A
B
C
D
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doubling the large mass
doubling the distance between the masses
reducing the small mass by half
reducing the distance between the masses by half
human error.
air resistance.
local fluctuations in gravity.
the mass of the object.
A red ball and a green ball are simultaneously thrown horizontally from the same
height. The red ball has an initial speed of 40 meters per second and the green ball has
an initial speed of 20 meters per second. Compared to the time it takes the red ball to
reach the ground, the time it takes the green ball to reach the ground will be:
A
B
C
D
the same.
twice as much.
half as much.
four times as much.
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13. As shown in the diagram below, an inflated balloon released from rest moves
horizontally with velocity v.
The velocity of the balloon is most likely caused by:
A
B
C
D
action-reaction.
centripetal force.
gravitational attraction.
rolling friction.
14. The graph below shows the relationship between weight and mass for a series of objects
on the Moon. The acceleration due to gravity on the Moon is approximately
A
B
C
D
0.63 m/s2
1.6 m/s2
9.8 m/s2
32 m/s2
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15. A communication satellite is in a circular orbit around Earth. If the speed of the
satellite is constant, the force acting on the satellite:
A
B
C
D
is zero.
is decreasing.
points toward the center of Earth at all times.
points in the direction that the satellite is moving.
16. The picture above shows the circular path of a toy plane being swung around on a
string. What path would the toy take if the string broke?
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17.
It took Jill 15 minutes to ride her bike 2 miles to the store. Then she rode 5 miles to a
park, which took 25 minutes. She ate lunch at the park for 30 minutes, and then took 20
minutes to ride 4 miles back to her house. What is her average speed over the entire
trip?
A
B
C
D
0.12 mi/hr
0.18 mi/hr
7.3 mi/hr
11 mi/hr
18. Compared to 8 kilograms of feathers, 6 kilograms of lead has:
A
B
C
D
less mass and less inertia.
less mass and more inertia.
more mass and less inertia.
more mass and more inertia.
19. Block A is pulled with constant velocity up an incline as shown in the diagram below.
Which arrow best represents the direction of the force of friction acting on block A?
A
B
C
D
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20. A student holds a book at rest in an outstretched hand. The force exerted on the book
by the student is equal to the book’s:
A
B
C
D
mass.
weight.
volume.
density.
21. A student attempts to measure the mass of a brick by measuring the force required to
accelerate it at 1 m/s2 on a level surface. The force required is 2 N, and the student
concludes that the brick has a mass of 2 kg. A balance shows that the mass of the brick
is really 1.5 kg. The experimental error is most likely due to:
A
B
C
D
gravity.
work.
friction.
inertia.
22. What is the magnitude of the net force acting on a 2.0 x 103-kilogram car as it
accelerates from rest to a speed of 15 meters per second in 5.0 seconds?
A
B
C
D
6.0 x 103 N
2.0 x 104 N
3.0 x 104 N
6.0 x 104 N
23. A soccer player kicks a 0.5-kilogram stationary ball with a force of 50 newtons. What is
the force on the player’s foot?
A
B
C
D
0N
10 N
50 N
100 N
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24. The diagram below shows an object with a mass of 1.0 kilogram attached to a string
0.50 meter long. The object is moving at a constant speed of 5.0 meters per second in a
horizontal circular path with center at point O.
While the object is undergoing uniform circular motion, its acceleration:
A
B
C
D
has a magnitude of zero.
is in the direction of travel.
is directed toward the center of the circle.
is directed away from the center of the circle.
25. The diagram below represents the orbit of a comet about the Sun.
At which position in its orbit is the comet’s speed greatest (A, B, C or D)?
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26. The picture shows two objects that were dropped and recorded with a stroboscopic
camera. The best explanation for the results is that object A:
A
B
C
D
has less air resistance.
was dropped from a greater height.
has a greater mass.
accelerated more slowly.
27. A truck collides head on with a small compact car. During the collision:
A the truck exerts a greater amount of force on the car than the car exerts on the
truck.
B the car exerts a greater amount of force on the truck than the truck exerts on the
car.
C the truck exerts the same amount of force on the car as the car exerts on the
truck.
D neither exerts a force on the other, the car gets smashed simply because it gets
in the way of the truck.
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28. A student applied a constant force to a toy truck. A graph of the truck’s movement is
shown below.
Which of the following could best explain the change in velocity at time X?
A
B
C
D
The truck’s momentum became greater than its inertia.
The truck went from moving in a straight path to moving in a curved path.
The truck began traveling up a slightly sloped surface.
The truck went from rolling on a rough surface to rolling on a polished surface.
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Open Ended
A car is traveling due north at 24.0 meters per second when the driver sees an obstruction
on the highway. The data table below shows the velocity of the car at 1.0-second intervals
as it is brought to rest on the straight, level highway.
Time (s)
0.0
1.0
2.0
3.0
4.0
Velocity (m/s)
24.0
19.0
14.0
9.0
4.0
A. Plot the data points for velocity versus time.
B. Draw the best-fit line.
C. Using your graph, determine the acceleration of the car.
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Physics Benchmark Exam #1 2009-2010
Answer Key
1.
2.
3.
4.
5.
6.
7.
8.
B
A
A
A
A
B
A
B
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
C
D
B
A
A
B
C
A
B
A
B
B
C
A
C
C
D
A
C
C
1.5 m/s (1a)
1.0 m/s (1a)
5.5 m/s (1a)
motion sensor. (1b)
2 m/s2 to the right (1c)
1.50 m/s2 (1c)
less than the speed limit (1b)
The scale reading will increase momentarily then will decrease as the student is moving
upward from the scale. (1d)
3.0 N south (1b)
reducing the distance between the masses by half (1e)
air resistance. (1e)
the same (1e)
action-reaction (1d)
1.6 m/s2 (1c)
points toward the center of Earth at all times. (1f)
(1g)
0.18 mi/hr (1a)
less mass and less inertia (1b)
(1b)
weight (1b)
friction. (I and E)
6.0 x 103 (1c)
50 N (1d)
is directed toward the center of the circle (1g)
(1f)
has less air resistance. (1e)
the truck exerts the same amount of force on the car as the car exerts on the truck. (1d)
The truck began traveling up a slightly sloped surface. (I and E)
Open ended- I and E/1b/1c
Score
3-high (all criteria
are met)
2-medium
1-low
0- very low
.
Criteria
 The graph has a title
 Labeled axes with units
 Independent and dependent variables are correctly placed
 Axes are numbered correctly
 Data is correctly plotted
 Correct answer is -5m/s2
One of the criteria is missing
2 or 3 of the criteria are missing
4 or more of the criteria are missing
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