An astronaut on a distant planet wants to determine its acceleration due to gravity. the astronaut throws a rock straight up with a velocity of +14.2 m/s and measures a time of 15.9 s before the rock returns to his hand. what is the acceleration (magnitude and direction) due to gravity on this planet? (positive = up, negative = down).

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final