A boy drops a ball from an observation tower. The ball hits the ground in 5.0 s. What is the ball's velocity at the time of impact?

A. 0 m/s

B. 98 m/s

C. 49 m/s

D. 123 m/s

An orange light (f = 5.2 * 10'4Hz) is shined on a tin surface. Assuming electrons are ejected, what is the voltage created?

Different between thrust and upthrust

The data table below lists the mass and speed of four different objects. which object has the greatest inertia? a. a b. b c. c d. d listen submit answer previous next

The 20 or so minerals that make up most of the rocks of earth's crust are know as what

spheres 1 and 2 both carry positive charge and are connected by insulating strings to a ceiling. when the two spheres hang in equilibrium, they hang at the same height, but sphere 1's string is more vertical.

A ball strikes a wall. It exerts a force of 10 N to the left against the wall and bounces off. What force does the wall exert on the ball?

A car slows down from 24 m/s to rest in a distance of 90 m. what was its acceleration, assumed constant? incorrect: your answer is incorrect. m/s2

Radar, the first link in the cosmic distance chain, is used to establish the baseline distance necessary for the second link, parallax. What baseline distance must we know before we can measure parallax?

What types of areas are more prone to floods?

would the phases of the moon be affected if the moon didn't make one rotation for each revolution of earth?