PHYS 1011 EXAM II QUESTIONS COMPLETE WITH 100%
VERIFIED ANSWERS
\.An object of mass m sits on a flat table. The Earth pulls on this object
with force mg, which we will call the action force. What is the reaction
force?
a. The table pulling upward on the Earth with force mg.
b. The table pushing up on the object with force mg.
c. The object pushing down on the table with force mg.
d. The object pulling upward on the Earth with force mg. - ANSWERS-d.
The object pulling upward on the Earth with force mg.
\.A space shuttle is in orbit around the earth at an altitude of 12,000
miles. Which one of the following statements best explains why the
astronauts experience "weightlessness?"
a. The space ship is in free fall; and its floor cannot press upwards on
the astronaut.
b. The centripetal force of the earth on the astronaut is zero newtons.
,c. The pull of the earth on the spaceship is canceled by the pull of the
other planets.
d. The force of the earth on the spaceship and the force of the
spaceship on the earth cancel because they are equal in magnitude, but
opposite in direction. - ANSWERS-a. The space ship is in free fall; and its
floor cannot press upwards on the astronaut.
\.A spaceship continues to fly towards the moon even after the engines
are shut off. If the moon's gravity is negligible, this illustrates:
a. Newton's Third Law
b. Newton's First Law
c. Newton's Law of Gravitation
d. Newton's Second Law - ANSWERS-b. Newton's First Law
\.Suppose you are playing hockey on a new-age ice surface for which
there is no friction between the ice and the hockey puck. You wind up
and hit the puck as hard as you can. After the puck loses contact with
your stick, the puck will
a. start to slow down.
b. not slow down or speed up.
c. speed up a little, and then slow down.
, d. speed up a little, and then move at a constant speed. - ANSWERS-b.
not slow down or speed up
\.A 5-N force and a 10-N force act on the same point of an object. The
5-N force acts due east while the 10-N force acts north. The resultant
force is
a. 8.66 N, northeast
b. 8.66 N, east
c. 11.2 N, northeast
d. 8.66 N, west - ANSWERS-c. 11.2 N, northeast
\.A block of mass M slides down a frictionless plane inclined at an angle
θ with the horizontal. The normal reaction force exerted by the plane
on the block is directed
a. toward the center of the Earth.
b. toward the center of mass of the block.
c. perpendicular to the plane.
d. parallel to the plane in the opposite direction as the movement of
the block - ANSWERS-c. perpendicular to the plane
VERIFIED ANSWERS
\.An object of mass m sits on a flat table. The Earth pulls on this object
with force mg, which we will call the action force. What is the reaction
force?
a. The table pulling upward on the Earth with force mg.
b. The table pushing up on the object with force mg.
c. The object pushing down on the table with force mg.
d. The object pulling upward on the Earth with force mg. - ANSWERS-d.
The object pulling upward on the Earth with force mg.
\.A space shuttle is in orbit around the earth at an altitude of 12,000
miles. Which one of the following statements best explains why the
astronauts experience "weightlessness?"
a. The space ship is in free fall; and its floor cannot press upwards on
the astronaut.
b. The centripetal force of the earth on the astronaut is zero newtons.
,c. The pull of the earth on the spaceship is canceled by the pull of the
other planets.
d. The force of the earth on the spaceship and the force of the
spaceship on the earth cancel because they are equal in magnitude, but
opposite in direction. - ANSWERS-a. The space ship is in free fall; and its
floor cannot press upwards on the astronaut.
\.A spaceship continues to fly towards the moon even after the engines
are shut off. If the moon's gravity is negligible, this illustrates:
a. Newton's Third Law
b. Newton's First Law
c. Newton's Law of Gravitation
d. Newton's Second Law - ANSWERS-b. Newton's First Law
\.Suppose you are playing hockey on a new-age ice surface for which
there is no friction between the ice and the hockey puck. You wind up
and hit the puck as hard as you can. After the puck loses contact with
your stick, the puck will
a. start to slow down.
b. not slow down or speed up.
c. speed up a little, and then slow down.
, d. speed up a little, and then move at a constant speed. - ANSWERS-b.
not slow down or speed up
\.A 5-N force and a 10-N force act on the same point of an object. The
5-N force acts due east while the 10-N force acts north. The resultant
force is
a. 8.66 N, northeast
b. 8.66 N, east
c. 11.2 N, northeast
d. 8.66 N, west - ANSWERS-c. 11.2 N, northeast
\.A block of mass M slides down a frictionless plane inclined at an angle
θ with the horizontal. The normal reaction force exerted by the plane
on the block is directed
a. toward the center of the Earth.
b. toward the center of mass of the block.
c. perpendicular to the plane.
d. parallel to the plane in the opposite direction as the movement of
the block - ANSWERS-c. perpendicular to the plane
