Question

if it were possible to remove gravity and friction, think about what would happen to a football if it were tossed into the air
assume the football is in a vacuum (no gravity or friction) and is continuously moving, which force(s) would be acting on
the ball?

a force must be
applied to it before
it slows to a
position of rest.

a force must be
applied to it when
it slows to a
position of rest.

no force is
needed; an object
in motion stays in
motion.

many forces must
act upon it to keep
it in motion.

Explanation:

This question is about Newton's first law of motion (inertia), which states that an object in motion will stay in motion with a constant velocity (same speed and direction) unless acted upon by a net external force. In the given scenario, gravity and friction (external forces) are removed. So, once the football is tossed (initial force to set it in motion), there are no forces acting on it to change its motion. The third option correctly reflects this: no force is needed to keep it moving as an object in motion stays in motion. The first two options imply a force is needed to stop it (but in this scenario, we're asked about forces acting while it's moving, and without external forces, it won't slow down on its own). The fourth option is incorrect as no net force is needed to keep an object in motion (only to change its motion).

Answer:

C. No force is needed; an object in motion stays in motion. (Assuming the third option is labeled C, as per typical multiple - choice formatting where the third box corresponds to option C. If the original question had different labeling, adjust the label but keep the text "No force is needed; an object in motion stays in motion".)