The output work of a machine compared to the input work is the efficiency of the machine.

True

Explanation:

Efficiency of machine is determined by dividing the work output by the work input and normally expressed as a percentage hence the above statement is true. Normally, the efficiency of a machine is not always 100% due to energy losses within machine parts. The energy losses are mainly attributed to friction hence methods of reducing friction within mechanical parts such as oiling and greasing are recommended to achieve higher mechanical efficiency.