If a freely falling rock hits the ground with a force of 245Newtons what is its mass?

Astudent is working in the lab to determine how time affect impulse the student keeps the force the same in each row but changes impact the time some data is shown witch trial has the greatest a student is working in the lab to determine how time affect impulse the student keeps the fours the same in each row but change is the impact time some data shown witch trial has the greatest impulse

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?

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?