Why are objects that fall near Earth's surface rarely in free fall? O Gravity does not act on objects near Earth's surface.
O Air exerts forces on falling objects near Earth's surface.
O The objects do not reach terminal velocity.
O The objects can be pushed upward by gravity.​

Avery hard rubber ball (m = 0.5 kg) is falling vertically at 4 m/s just before it bounces on the floor. the ball rebounds back at essentially the same speed. if the collision with the floor lasts 0.05 s, what is the average force exerted by the floor on the ball?

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.