If the effects of heat and friction are ignored, the amount of work output is always <u>same as</u> the amount of work input, even when using a simple machine.
Simple machines make work easier, but they do not decrease the amount of work one has to do.
A simple machine can change the amount of force applied to an object, and the distance over which the force is applied.
<em><u>The efficiency of simple machines is the ratio of work output to work input as a percentage. However, the efficiency is never 100% due to heat and friction. Therefore, if heat and friction then the efficiency would be 100% which means that the work input is equal to the work output.</u></em>
<span>D is at rest at the top of a 2 m high slope. The sled has a mass of 45 kg. The sled's potential energy is J? </span>Answer: The sled's potential energy is 882 Joules
