An electric motor operates on a 50,V supply a | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The efficiency $\eta$ of an electric motor is given by the ratio of back $EMF$ $e$ to the supply voltage $E$: $\eta = \frac{e}{E} 	imes 100$.Give

Vedclass · Accepted Answer

$2.9$

Vedclass · Answer

(C) The efficiency $\eta$ of an electric motor is given by the ratio of back $EMF$ $e$ to the supply voltage $E$: $\eta = \frac{e}{E} 	imes 100$.Given $\eta = 30\% = 0.3$,we have $e = 0.3 	imes E = 0.3 	imes 50\,V = 15\,V$.The current $i$ in the motor is given by $i = \frac{E - e}{R}$,where $R$ is the resistance of the winding.Substituting the given values: $12 = \frac{50 - 15}{R}$.$12 = \frac{35}{R}$.$R = \frac{35}{12} \approx 2.916\,\Omega$.Rounding to one decimal place,we get $R = 2.9\,\Omega$.

An electric motor operates on a $50\,V$ supply and a current of $12\,A$. If the efficiency of the motor is $30\%$,what is the resistance of the winding of the motor in $\Omega$?

Similar Questions

When the speed of a $dc$ motor increases, the armature current:

The armature of a generator of resistance $1 \,\Omega$ is rotated at its rated speed and produces $125 \,V$ without load and $115 \,V$ with full load. The current in the armature coil is ......... $A$.

$A$ motor operating on $100 \ V$ draws a current of $1 \ A$. If the efficiency of the motor is $91.6 \%$,then the loss of power in units of $cal/s$ is

In an $AC$ generator,the ends of the coil are connected to

An electric fan operates on the principle of which of the following?

Vedclass Test Series

Exam Paper Generator

Online Exam Module