Efficiency of a machine is lesser than 100% , Why?

Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work). The output work is always less than the input work because some of the input work is used to overcome friction. Therefore, efficiency is always less than 100 percent.

0.93xc=0.93x3x10^8m/s

2.54cm is 1 inch

360seconds i 1 hr