Why is the work output of any real machine less than the work needed to operate it? fricton reduce the work input

work is gained due to friction

work lost due to friction

work lost due to friction

Explanation:

The work output of any real machine is usually less than the work needed to operate the machine due to the fact that some input work is lost due to friction.

Frictional forces are those forces that oppose the motion of 2 surfaces sliding against each other and this is one of the reasons machines do not work at 100% efficiency. When the opposition happens, some of the input work is converted to heat.

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

why do the isotopes of a particular element behave differently in nuclear reactions but the same in chemical reactions? chemical reactions involve changes to electrons in an atom; isotopes do not differ in electrons, and so they react the same way during chemical changes.