Why is combustion of fuel necessary for heat engines to do work?

A500g object falls off a cliff and losers 100 j from its gravitational potential energy store. if the gravitational field strength g=9.8n/kg, how high is the cliff?

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

Use the drop-down menus to answer each question. which line represents the movement of a cart with a constant acceleration? a which line represents the movement of a cart with a constant velocity? c which lines represents a cart with no velocity or acceleration? b