PHY 121: RQ 06 – 09 Question and
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You are standing in a moving bus, facing forward, and you suddenly fall
forward as the bus comes to an immediate stop. The force acting on you that
causes you to fall forward is - correct answer ✔No forces were acting on you
to cause you to fall.
A woman is straining to lift a large crate, without success because it is too
heavy. We denote the forces on the crate as follows: P is the upward force the
woman exerts on the crate, C is the vertical contact force exerted on the crate
by the floor, and W is the weight of the crate. How are the magnitudes of
these forces related while the woman is trying unsuccessfully to lift the crate?
- correct answer ✔P + C = W
If you swing a bucket of water fast enough in a vertical circle, at the highest
point the water does not spill out because an outward force balances the pull
of gravity on the water. - correct answer ✔false
Suppose a highway curve is properly banked to eliminate friction for a speed
of 45 mph. If your tires were bald and you wanted to avoid sliding on the road,
you would have to drive - correct answer ✔at exactly 45 mph.
A crate is sliding down an inclined ramp at a constant speed of 0.55 m/s. The
vector sum of all the forces acting on this crate must point down the ramp. -
correct answer ✔false
An object moves in a circular path at a constant speed. What is the direction
of the net force acting on the object? - correct answer ✔The net force is
directed toward the center of the circular path.
, An object is hanging by a string from the ceiling of an elevator. The elevator is
slowing down while moving upward. What is the magnitude of the tension in
the string? - correct answer ✔The magnitude of the tension in the string is
less than the magnitude of the weight of the object.
A box of mass m is pulled with a constant acceleration a along a horizontal
frictionless floor by a wire that makes an angle of 15° above the horizontal. If
T is the tension in this wire, then - correct answer ✔T > ma
Two identical cars are driving in opposite directions at the same speed. Their
kinetic energies have ____. - correct answer ✔the same magnitude and sign
If the net work done on an object is zero, what can you determine about the
object's kinetic energy? - correct answer ✔The object's kinetic energy
remains the same.
An object weighing 20 N moves horizontally toward the right a distance of 5.0
m. What is the work done on the object by the force of gravity? - correct
answer ✔The work done on the object by the force of gravity is zero joules.
A ball is thrown straight upward. How does the sign of the work done by
gravity while the ball is traveling upward compare with the sign of the work
done by gravity while the ball is traveling downward? - correct answer
✔Work done by gravity is negative while the ball is traveling upward and
positive while the ball is traveling downward.
If the net work done on an object is positive, what can you conclude about the
object's motion? - correct answer ✔The object is speeding up.
answers rated A+ 2025
You are standing in a moving bus, facing forward, and you suddenly fall
forward as the bus comes to an immediate stop. The force acting on you that
causes you to fall forward is - correct answer ✔No forces were acting on you
to cause you to fall.
A woman is straining to lift a large crate, without success because it is too
heavy. We denote the forces on the crate as follows: P is the upward force the
woman exerts on the crate, C is the vertical contact force exerted on the crate
by the floor, and W is the weight of the crate. How are the magnitudes of
these forces related while the woman is trying unsuccessfully to lift the crate?
- correct answer ✔P + C = W
If you swing a bucket of water fast enough in a vertical circle, at the highest
point the water does not spill out because an outward force balances the pull
of gravity on the water. - correct answer ✔false
Suppose a highway curve is properly banked to eliminate friction for a speed
of 45 mph. If your tires were bald and you wanted to avoid sliding on the road,
you would have to drive - correct answer ✔at exactly 45 mph.
A crate is sliding down an inclined ramp at a constant speed of 0.55 m/s. The
vector sum of all the forces acting on this crate must point down the ramp. -
correct answer ✔false
An object moves in a circular path at a constant speed. What is the direction
of the net force acting on the object? - correct answer ✔The net force is
directed toward the center of the circular path.
, An object is hanging by a string from the ceiling of an elevator. The elevator is
slowing down while moving upward. What is the magnitude of the tension in
the string? - correct answer ✔The magnitude of the tension in the string is
less than the magnitude of the weight of the object.
A box of mass m is pulled with a constant acceleration a along a horizontal
frictionless floor by a wire that makes an angle of 15° above the horizontal. If
T is the tension in this wire, then - correct answer ✔T > ma
Two identical cars are driving in opposite directions at the same speed. Their
kinetic energies have ____. - correct answer ✔the same magnitude and sign
If the net work done on an object is zero, what can you determine about the
object's kinetic energy? - correct answer ✔The object's kinetic energy
remains the same.
An object weighing 20 N moves horizontally toward the right a distance of 5.0
m. What is the work done on the object by the force of gravity? - correct
answer ✔The work done on the object by the force of gravity is zero joules.
A ball is thrown straight upward. How does the sign of the work done by
gravity while the ball is traveling upward compare with the sign of the work
done by gravity while the ball is traveling downward? - correct answer
✔Work done by gravity is negative while the ball is traveling upward and
positive while the ball is traveling downward.
If the net work done on an object is positive, what can you conclude about the
object's motion? - correct answer ✔The object is speeding up.
