When the sound source is moving away from the receiver, the waves spread out and the frequency decreases – the receiver perceives this as a pitch.

Occurs when an energy source transfers heat directly to another subject space; an example would be an object becoming warm by sitting in the sunshine

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

Often called simply "velocity," this is the velocity of an object at a particular moment in time.