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An electric motor runs a D.C. source of ...

An electric motor runs a `D.C.` source of e.m.f. `200 V` and draws a current of `10A`. If the efficiency is `40%`, then ressistance of the armature is:

A

`5Omega`

B

`12 Omega`

C

`120Omega`

D

`160 Omega`

Text Solution

Verified by Experts

The correct Answer is:
B
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AAKASH INSTITUTE-ELECTROMAGNETIC INDUCTION-Assignment (SECTION - A)
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  2. Dimensional formula of self-inductance is

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  4. A metalic ring is dropped down, keeping its plane perpendicular to a c...

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  6. Coefficient of coupling between two coils of self-inductances L(1) and...

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  7. There is a uniform magnetic field directed perpendicular and into the ...

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  8. A square loop of wire with side length 10 cm is placed at angle of 45^...

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  9. A uniformly wound solenoid coil of self inductance 1.8xx10^(-4)H and r...

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  10. The magnitude opf the earth's magnetic field at a place is B(0) and th...

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  11. Two parallel rails of a railway track insulated from each other and wi...

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