PHYS 141 EXAM 2 CONCEPT EXAM
QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE 2026
GRADE A+.PDF
Consider the following situations:
(i) A minivan is following a hairpin turn on a mountain road at a constant speed
of twenty miles per hour.
(ii) A parachutist is descending at a constant speed 10 m/s.
(iii) A heavy crate has been given a quick shove and is now sliding across the
floor. There is friction between the crate and floor.
(iv) A child is swinging back and forth on a swing at the park.
(v) A football that was kicked is flying through the goal posts.
In which one of these situations does the object or person experience zero
acceleration?
8
a) i only
b) ii only
c) iii and iv only
d) iv and v only
e) all of the situations - answer-B
A pendulum bob of mass m is attached to
the ceiling by a thin wire of length L. The
bob moves at constant speed in a
horizontal circle of radius R, with the wire
making a constant angle β with the vertical.
, The tension in the wire
A. is greater than mg.
B. is equal to mg.
C. is less than mg.
D. could be two of the above, depending on the values of
m, L, R, and β.
E. could be all three of the above, depending on the values
of m, L, R, and β. - answer-A
The Moon does not crash into Earth because
22
a) it's in Earth's gravitational field.
b) the net force on it is zero.
c) it is beyond the main pull of Earth's gravity.
d) it's being pulled by the Sun as well as by Earth.
e) none of the above - answer-E, The Moon does not crash into Earth because of its high
speed tangential to
its path. If it slowed down or stopped moving all together, it would, of
course, fall directly into Earth. With its high speed, the Moon would fly off
into space if it weren't for gravity providing the centripetal force.
Concept Question 1
13
An elevator is being lifted at a constant speed by a
steel cable attached to an electric motor. Which
statement is correct?
A. The cable does positive work on the elevator, and the
elevator does positive work on the cable.
QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE 2026
GRADE A+.PDF
Consider the following situations:
(i) A minivan is following a hairpin turn on a mountain road at a constant speed
of twenty miles per hour.
(ii) A parachutist is descending at a constant speed 10 m/s.
(iii) A heavy crate has been given a quick shove and is now sliding across the
floor. There is friction between the crate and floor.
(iv) A child is swinging back and forth on a swing at the park.
(v) A football that was kicked is flying through the goal posts.
In which one of these situations does the object or person experience zero
acceleration?
8
a) i only
b) ii only
c) iii and iv only
d) iv and v only
e) all of the situations - answer-B
A pendulum bob of mass m is attached to
the ceiling by a thin wire of length L. The
bob moves at constant speed in a
horizontal circle of radius R, with the wire
making a constant angle β with the vertical.
, The tension in the wire
A. is greater than mg.
B. is equal to mg.
C. is less than mg.
D. could be two of the above, depending on the values of
m, L, R, and β.
E. could be all three of the above, depending on the values
of m, L, R, and β. - answer-A
The Moon does not crash into Earth because
22
a) it's in Earth's gravitational field.
b) the net force on it is zero.
c) it is beyond the main pull of Earth's gravity.
d) it's being pulled by the Sun as well as by Earth.
e) none of the above - answer-E, The Moon does not crash into Earth because of its high
speed tangential to
its path. If it slowed down or stopped moving all together, it would, of
course, fall directly into Earth. With its high speed, the Moon would fly off
into space if it weren't for gravity providing the centripetal force.
Concept Question 1
13
An elevator is being lifted at a constant speed by a
steel cable attached to an electric motor. Which
statement is correct?
A. The cable does positive work on the elevator, and the
elevator does positive work on the cable.
