Question

A girl throws a rock horizontally with a velocity of 10 m/s from a bridge. What is the initial horizontal velocity of the rock?

1) 0 m/s
2) 10 m/s
3) 20 m/s
4) Cannot be determined

Answer 1

The initial horizontal velocity of the rock is 10 m/s, as it remains constant in horizontal projectile motion when air resistance is ignored.

Step-by-step explanation:

The initial horizontal velocity of the rock thrown horizontally from a bridge is 10 m/s. Since the girl throws the rock with a horizontal velocity, this velocity remains constant in the absence of air resistance due to the principle of inertia. In projectile motion, the horizontal motion and vertical motions are independent of each other. The initial vertical velocity in this case would be 0 m/s because the rock is only given horizontal velocity.