Download 7.5 Test Review- Circular Motion and Gravitation

Name: _______________________________
Date: ___________
Physics
Test Review: Newton’s Law of Universal Gravitation and Circular Motion
Base your questions to number 1-3 on the diagram and
At the moment shown in the diagram, what are the
information below
correct directions of both the velocity and
centripetal acceleration of the ball?
The diagram shows a 2.0-kilogram model airplane attached
to a wire. The airplane is flying clockwise in a horizontal
circle of radius 20. meters at 30. meters per second.
a.
b.
c.
d.
1. The centripetal force acting on the airplane at the
position shown is directed toward point
a.
A
c.
C
b. B
d. D
2. What is the magnitude of the centripetal
acceleration of the airplane?
a. 0 m/s2
b. 1.5 m/s2
c. 45 m/s2
d. 90. m/s2
3. If the wire breaks when the airplane is at the
position shown, the airplane will move toward
point
a.
A
c.
C
b. B
d. D
4. A motorcycle travels around a flat circular track. If
the speed of the motorcycle is increased, the force
required to keep it in the same circular path
a. Decreases
b. Increases
c. Remains the same
6. A 3.0-kilogram mass is traveling in a circle of 0.20meter radius with a speed of 2.0 meters per
second. What is the centripetal acceleration?
a. 10. m/s2
b. 20. m/s2
c. 60. m/s2
d. 6.0 m/s2
7. A car going around a curve is acted upon by a
centripetal force, F. If the speed of the car were
twice as great, the centripetal force necessary to
keep it moving in the same path would be
a.
F
c.
F/2
b. 2F
d. 4F
Base your answers to questions 8-11 on the diagram and
information below.
The diagram shows an object with a mass of 1.0 kg 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.
5. The diagram below shows a ball undergoing
uniform circular motion as it travels clockwise on a
string.
8. What is the magnitude of the centripetal force
acting on the object?
a. 2.5 N
b. 10. N
c. 25 N
d. 50. N
9. While the object is undergoing uniform circular
motion, its acceleration
a. has a magnitude of zero
b. increases in magnitude
c. is directed toward the center of the circle
d. is directed away from the center of the circle
Base your answers to questions 14-15 on the information
and diagram below.
A vehicle travels at a constant speed of 6.0 meters per
second around a horizontal circular curve with a radius of
24 meters. The mass of the vehicle is 4.4 × 103 kilograms.
An icy patch is located at P on the curve.
10. If the string is cut when the object is at the position
shown, the path the object will travel from this
position will be
a. toward the center of the circle
b. a curve away from the circle
c. a straight line tangent to the circle
11. If the string is lengthened while the speed of the
object remains constant, the centripetal
acceleration of the object will
a. Decrease
b. Increase
c. Remain the same
12. An object with a mass of 0.5 kilogram is swung by a
string in a horizontal circle of radius 1 meter at a
speed of 2 meters per second. The magnitude of
the force on the mass is
a. 1 N
b. 2 N
c. 0.5 N
d. 4 N
13. Two masses, A and B, move in circular paths as
shown in the diagram.
14. What is the magnitude of the frictional force that
keeps the vehicle on its circular path?
a. 1.1x103 N
b. 6.6x103 N
c. 4.3x104 N
d. 6.5x104 N
15. On the icy patch of pavement, the frictional force of
the vehicle is zero. Which arrow best represents
the direction of the vehicle's velocity when it
reaches icy patch P?
a.
b.
c.
d.
The centripetal acceleration of mass A, compared
to that of mass B, is
a. The same
b. Twice as great
c. One-half as great
d. Four times as great
Base your answers to questions 16-17 on the information
and diagram below.
A 60.-kilogram adult and 30.-kilogram child are passengers
on a rotor ride at an amusement park. When the rotating
hollow cylinder reaches a certain constant speed, v, the
floor moves downward. Both passengers stay "pinned"
against the wall of the rotor, as shown in the diagram.
16. The magnitude of the frictional force between the
adult and the wall of the spinning rotor is F. What is
the magnitude of the frictional force between the
child and the wall of the spinning rotor?
a.
F
c.
½F
b. 2F
d. ¼ F
17. Compared to the magnitude of the acceleration of
the adult, the magnitude of the acceleration of the
child is
a. Less
b. Greater
c. The same
Base your answers to questions 18-20 on the information
and diagram below.
A 4.0-kilogram model airplane travels in a horizontal
circular path of radius 12 meters at a constant speed of 6.0
meters per second.
18. At the position shown, what is the direction of the
net force acting on the airplane?
a.
North
c.
East
b. South
d. West
19. What is the magnitude of the centripetal
acceleration of the airplane?
a. 0.50 m/s2
b. 2.0 m/s2
c. 3.0 m/s2
d. 12 m/s2
20. If the speed of the airplane is doubled and the
radius of the path remains unchanged, the
magnitude of the centripetal force acting on the
airplane will be
a. Half as much
b. Twice as much
c. One-fourth as much
d. Four times as much
21. When a satellite is at a distance d from the center
of the Earth, the force due to gravity on the satellite
is F. What would the force due to gravity on the
satellite be when its distance from the center of the
Earth is 3d?
a.
F
c.
F/3
b. F/9
d. 9F
22. What is the gravitational force of attraction
between a planet and a 17-kilogram mass that is
falling freely toward the surface of the planet at 8.8
meters per second squared?
a. 150 N
b. 8.8 N
c. 1.9 N
d. 0.52 N
23. If the Earth were twice as massive as it is now, then
the gravitational force between it and the Sun
would be
a. The same
b. Twice as great
c. Half as great
d. Four times as great
24. Two point masses are located a distance, D, apart.
The gravitational force of attraction between them
can be quadrupled by changing the distance to
a.
D/2
c.
D/4
b. 2D
d. 4D
25. Which graph best represents the relationship
between the masses of different objects and the
gravitational force acting on them near the Earth's
surface?
a.
c.
b.
d.
26. Gravitational force of attraction F exists between
two point masses A and B when they are separated
by a fixed distance. After mass A is tripled and mass
B is halved, the gravitational attraction between the
two masses is
a.
1/6 F
c.
3/2 F
b. 2/3 F
d. 6F
27. The diagram shows spheres A and B with masses of
M and 3M, respectively.
If the gravitational force of attraction of sphere A
on sphere B is 2 newtons, then the gravitational
force of attraction of sphere B on sphere A is
a.
9N
c. 3 N
b. 2 N
d. 4 N
28. The magnitude of the gravitational force between
two objects is 20. newtons. If the mass of each
object were doubled, the magnitude of the
gravitational force between the objects would be
a.
5.0 N
c. 20. N
b. 10. N
d. 80. N
29. The magnitude of the gravitational force of
attraction between Earth and the Moon is
approximately
a. 2.1x1020 N
b. 6.0x1024 N
c. 6.7x10-11 N
d. 7.8x1028 N
30. What is the magnitude of the gravitational force
between an electron and a proton separated by a
distance of 1.0 × 10-10 meter?
a. 1.0x10-47 N
b. 1.5x10-46 N
c. 1.0x10-37 N
d. 1.5x10-36 N
31. The gravitational force of attraction between two
objects would be increased by
a. doubling the mass of both objects, only
b. doubling the distance between the objects, only
c. doubling the mass of both objects and doubling
the distance between the objects
d. doubling the mass of one object and doubling
the distance between the objects
32. The centers of two 15.0-kilogram spheres are
separated by 3.00 meters. The magnitude of the
gravitational force between the two spheres is
approximately
a. 1.11x10-10 N
b. 3.34x10-10 N
c. 1.67x10-9 N
d. 5.00x10-9 N
33. The graph below represents the relationship
between gravitational force and mass for objects
near the surface of Earth.
The slope of the graph represents the
a. acceleration due to gravity
b. universal gravitational constant
c. momentum of objects
d. weight of objects
34. The gravitational force of attraction between Earth
and the Sun is 3.52 × 1022 newtons. Use this
information to calculate the mass of the Sun.
35. The diagram represents two satellites of equal
mass, A and B, in circular orbits around a planet.
Compared to the magnitude of the gravitational
force of attraction between satellite A and the
planet, the magnitude of the gravitational force of
attraction between satellite B and the planet is
a. Half as great
b. Twice as great
c. One-fourth as great
d. Four times as great
Base your answers to questions 36-37 on the information
below.
Io (pronounced “EYE oh”) is one of Jupiter’s moons
discovered by Galileo. Io is slightly larger than Earth’s
Moon.
The mass of Io is 8.93 × 1022 kilograms and the mass of
Jupiter is 1.90 × 1027 kilograms. The distance between the
centers of Io and Jupiter is 4.22 × 108 meters.
36. Calculate the magnitude of the gravitational force
of attraction that Jupiter exerts on Io.
a. Fg = 5.35x1020 N
b. Fg = 6.35x1022 N
c. Fg = 6.35x10-22 N
d. Fg = 6.24x102 N
37. Calculate the magnitude of the acceleration of Io
due to the gravitational force exerted by Jupiter.
a. a = 7.12 m/s2
b. a = 0.0712 m/s2
c. a = 0.712 m/s2
d. a = 0.00712 m/s2
38. Which diagram best represents the gravitational
forces, Fg, between a satellite, S, and Earth?
a.
c.
b.
d.
39. When Earth and the Moon are separated by a
distance of 3.84 × 108 meters, the magnitude of the
gravitational force of attraction between them is
2.0 × 1020 newtons. What would be the magnitude
of this gravitational force of attraction if Earth and
the Moon were separated by a distance of 1.92 ×
108 meters?
a. 5.0x1019 N
b. 2.0x1020 N
c. 4.0x1020 N
d. 8.0x1020 N
40. A space probe is launched into space from Earth’s
surface. Which graph represents the relationship
between the magnitude of the gravitational force
exerted on Earth by the space probe and the
distance between the space probe and the center
of Earth?
a.
c.
b.
d.
Answer Key
1. C
2. C
3. B
4. B
5. A
6. B
7. D
8. D
9. C
10. C
11. A
12. B
13. B
14. B
15. D
16. C
17. C
18. C
19. C
20. D
21. B
22. A
23. B
24. A
25. D
26. C
27. B
28. D
29. A
30. A
31. A
32. C
33. A
34. 1.99
35. C
36. B
37. C
38. C
39. D
40. B