Question

efficiency is the ratio of work output to work input. it is expressed as a percentage (%). the higher the percentage (%), the higher the efficiency of the machine. work input is the amount of work put into a machine. work output is the amount of work done by the machine. friction is the opposing force one object exerts on another when they touch. an ideal machine is 100% efficient and it loses no work due to friction. ideal machines do not exist! choose the correct answer an ideal machine is a machine with 100% efficiency. do ideal machines exist in the real world? no yes we do not know

Explanation:

In the real world, machines experience friction, which causes energy (work) loss. An ideal machine has 100% efficiency (no work loss due to friction), but since friction exists in real - world machines, ideal machines (with 100% efficiency) do not exist.

Answer:

No