The armature of a DC motor has 20Omega r...

The armature of a `DC` motor has `20Omega` resistance. It draws a current of `1.5 A` when run by `200 V DC` supply The value of back emf induced in it will be

`150V`

`170V`

`180V`

`190V`

Text Solution

Verified by Experts

The correct Answer is:

Back emf = Applied voltage potential drop across armature coil
`=200-iR`
`=200-1.5xx20`
`=170V`

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