Bob, who has a mass of 72 kg , can throw a 480 g rock with a speed of 28 m/s. The distance through which his hand moves as he accelerates the rock forward from rest until he releases it is 1. 0 m.

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

20. threshold braking in the vehicle's braking system occurs when a. the brake pedal is pushed, heel on floorboard, with full foot pressure. b. the brakes are exerting full braking power, without traction loss. c. the driver begins pushing down the brake pedal, with moderate slowdown. d. the brakes just begin to take hold with a gradual slowdown.