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Grade 11 - Physics
Chapter 4 - Assignment
Name: ___________________
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Which of the following statements is not correct?
a. Weight and force have both magnitude and direction.
b. The weight of a body on Earth is a measure of the gravitational attraction of Earth on that
body.
c. Gravitational force is a scalar quantity because it has magnitude only.
d. The gravitational mass of a body depends on its surroundings and altitude.
____
2. The equation for the net force that acts on a feather falling in a vacuum on Earth is
a.
c.
b.
d.
____
3. Considering gravitational and inertial mass, which statement is not correct? Both the gravitational mass and
the inertial mass of an object
a. have the same magnitude
c. are measured in the same way
b. have the same units
d. are not affected by location
____
4. What happens to the magnitude of the gravitational field strength if the distance from a planet doubles and the
test mass quadruples? The gravitational field strength
a. doubles
c. halves
b. remains the same
d. quarters
____
5. Inertial mass differs from gravitational mass in that inertial mass
a. is not additive for a number of different pure substances
b. cannot be measured on the surface of Earth
c. can be measured only when there is a uniform acceleration
d. can be measured only when there is constant velocity
____
6. A bronze statue is placed on an equal-arm balance and requires a 12-kg mass to balance it. When the statue is
hung from a spring scale, calibrated in kilograms, the reading on Earth is 12 kg. The equal-arm balance,
spring scale, standard masses, and object are transported to the Moon. If the force of gravity is 6.0 times
greater on Earth than on the Moon, what will be the readings on the equal-balance and on the spring scale on
the Moon?
a. equal-arm balance — 12 kg; spring scale — 12 kg
b. equal-arm balance — 12 kg; spring scale — 2.0 kg
c. equal-arm balance — 12 kg; spring scale — 72 kg
d. equal-arm balance — 2.0 kg; spring scale — 2.0 kg
____
7. The universal gravitational constant is G = 6.67  10–11 m3/(kg·s2).
The gravitational force of attraction between two spheres of mass 2.0 kg each, whose centres are separated by
2.0 m, is
a. 4.0 N
b. 6.7  10–11 N
____
c. 2.0
d. 4.0
6.7  10–11 N
6.7  10–11 N
8. Planet X has the same mass as planet Earth but twice the diameter.
What is the ratio of the force of gravity at the surface of planet X to the force of gravity at the surface of
planet Earth?
a. 1:2
b. 2:1
____
c. 1:4
d. 4:1
9.
The diagram shows three locations in the
path of an imaginary planet travelling in its
orbit about a star S.
At what point in its orbit is the magnitude of
the gravitational force of the star on the
planet the largest?
a.
b.
c.
d.
I
II
III
The gravitational force on the planet is the same at all locations.
____ 10. An astronaut is standing on the surface of the Moon. Assume that the Moon suddenly shrinks to one-half its
original diameter, but that its mass remains unchanged.
What will happen to the force of gravity acting on the astronaut?
a. It will remain unchanged.
b. It will become twice as great.
c. It will become four times greater.
d. It will become half as great.
____ 11. A toy rocket on the surface of Earth (radius r) experiences a gravitational force of magnitude 90.0 N.
What gravitational force will the same rocket experience in orbit at a distance of 3r from the centre of Earth?
a. zero
b. 10.0 N
____ 12. A satellite has a mass m and a weight
c. 30.0 N
d. 810 N
in a lab on the surface of Earth. It is placed in a rocket and sent to a
distance of two Earth radii above the surface of Earth.
As it travels from Earth to this new location, which of the following is correct?
a. The mass of the satellite decreases and the weight remains constant.
b. The mass of the satellite remains constant and its weight decreases.
c. Both the mass of the satellite and its weight remain constant.
d. Both the mass of the satellite and its weight decrease.
____ 13.
The modern torsion balance
shown is used to investigate
the relationship among the
force of gravity, Fg, the
masses, m and M, and their
separation, d. The deflection
of the beam is a measure of the
force of gravity between the
masses.
If both large masses, M, are
moved so that the separation
between m and M becomes
twice as large (2 d), what will
happen to the force of gravity
measured by the torsion
balance?
a.
b.
c.
d.
The force of gravity will quarter.
The force of gravity will halve.
The force of gravity will double.
The force of gravity will quadruple.
____ 14. A physics student stands on a bathroom scale, calibrated in newtons, while riding in an elevator. How will the
reading on the bathroom scale compare to the normal reading for the following sequence of the elevator’s
motion?
Elevator starts to descend; elevator descends at constant velocity; elevator stops descending.
a. heavier; normal; heavier
b. lighter; normal; heavier
c. heavier; normal; lighter
d. lighter; normal; lighter
____ 15. A scientist in a special elevator in a research facility on Earth, where
[down], is standing on a
bathroom scale, calibrated in newtons. The elevator can be given various vertical accelerations. The scientist
weighs himself and finds that his weight has apparently doubled.
What is the acceleration of the elevator?
a. 4.9 m/s2 [up]
b. 9.8 m/s2 [up]
c. 15 m/s2 [up]
d. 20 m/s2 [up]
____ 16. Which of the following statements concerning the magnitude of the gravitational field strength, g, on Earth
are correct?
I
II
III
On Earth, gravitational field strength increases as we move from either pole toward the
equator.
Gravitational field strength is larger near large gold deposits than near large zinc
deposits.
On Earth, gravitational field strength increases with depth in a deep zinc mine shaft.
Choose your answer from the following.
a. I and II only
b. I and III only
c. II and III only
d. I, II, and III
____ 17.
An 80.0-kg athlete is shown standing on a
bathroom scale in an elevator in a fitness
centre on Earth, where the magnitude of the
gravitational field strength, , is 9.81 N/kg.
The reading on the bathroom scale is 785 N.
Which statement(s) below is/are correct for
the motion of the elevator?
I
II
III
The elevator may be at rest.
The elevator may be moving up or down at constant speed.
The elevator may be accelerating up or down at 9.81 m/s2.
Choose your answer from the following.
a. I only
b. II only
c. III only
d. I and II only
____ 18.
A 100.0-kg astronaut is standing on a scale in
a rocket. The rocket is leaving the surface of
Earth with an acceleration of 9.81 m/s2 [up].
The gravitational field strength on Earth’s
surface is 9.81 N/kg [down].
What is the reading on the scale during
liftoff?
a. zero
b. 9.81  102 N [up]
c. 9.81  102 N [down]
d. 1.96  103 N [down]
____ 19. Which of the following statements is true for an astronaut in free fall in a space craft circling Earth?
a. The astronaut is truly weightless.
b. The astronaut is accelerating at 9.81 m/s2 toward Earth.
c. The astronaut has an apparent weight of zero.
d. The net force acting on the astronaut is zero.
Numeric Response
20. On planet 518c, a 45.0-g golf ball has a weight of 0.981 N. The gravitational field strength on planet 518c is
_____ N/kg. (Record your three-digit answer on the answer sheet.)
21. Use the following information to answer the next question.
According to the graph above, the gravitational field strength in Banff, AB is ______ N/kg. (Record your
three-digit answer on the answer sheet.)
22. The largest single rock brought back by Apollo mission astronauts is the Big Muley. If this moon rock had a
weight of 18.95 N on the Moon (a = 1.62 N/kg), its weight on Earth, expressed in scientific notation, is b 
10w N. The value of b is_______. (Record all three digits of your answer on the answer sheet.)
23. Mercury has a mass of 3.30  1023 kg and a radius of 2.44  106 m. The gravitational field strength on the
surface of Mercury is _____ N/kg. (Record your three-digit answer on the answer sheet.)
24. If a 95.0-kg astronaut’s apparent weight during takeoff is 2.69  103 N, the magnitude of the acceleration of
the rocket must be ____ m/s2. (Record your three-digit answer on the answer sheet.)
Essay
25. An 80.0-kg astronaut in a spaceship above Earth has a weight of 657 N.
(a) What is the value of g at the astronaut’s location?
(b) What is the distance of the astronaut from the centre of Earth