A stone falls from rest from the top of a cliff. A second stone is thrown downward from the same height 2.1 s later with an initial speed of41.16 m/s. They hit the ground at the sametime. How long does it take the first stone to hit the ground? The acceleration of gravity is 9.8 m/s2.Answer in units of s.

The graph below represents the work done by a student while running up flights of stairs. determine the student's power output after 10 seconds: 1600 j/s 8000 j/s 160 j/s 800 j/s

Aball tossed vertically upward from the ground next to a building passes the bottom of a window 1.8 s after being tossed and passes the top of the window 0.20 s later. the window is 2.0 m high from top to bottom. what was the ball's initial velocity? the unit vector j^ is directed upward. how far is the bottom of the window from the launch position? how high does the ball rise above the launch position?

Arocket starts from rest and moves upward from the surface of the earth. for the first 10.0 s of its motion, the vertical acceleration of the rocket is given by ay = 12.80 m/s32t, where the +y-direction is upward. (a) what is the height of the rocket above the surface of the earth at t = 10.0 s? b) what is the speed of the rocket when it is 325 m above the surface of the earth?