In an air-free chamber, a pebble is thrown horizontally, and at the same instant a second pebble is dropped from the same height. Compare the times of fall of the two pebbles.
A) The dropped pebble hits first.
B) The thrown pebble hits first.
C) They hit at the same time.
D) We cannot tell without knowing which pebble is heavier.

Question

Quizplus · Accepted Answer

In the absence of air resistance, the only force acting on both pebbles is gravity. This means both pebbles accelerate downward at the same rate, regardless of their horizontal velocities. Therefore, they hit the ground at the same time.

In an Air-Free Chamber, a Pebble Is Thrown Horizontally, and at the Same