An Electrical Motor Has a Degree of Efficiency ( Eff $P _ { 0 }$

Multiple Choice

An electrical motor has a degree of efficiency ( Eff ) equal to the ratio of its useful output power ( $P _ { 0 }$ ) to the input power ( $p _ { 1 }$ ) required to operate it.

A) $E f f = \frac { P _ { 0 } } { P _ { 1 } }$
B) $E f f = \frac { P _ { 1 } } { P _ { 2 } }$
C) $E f f = \frac { P ^ { 2 } 0 } { P _ { 1 } }$
D) $E f f = \frac { P _ { 1 } } { P _ { 0 } }$