The back emf in a DC motor is maxi...

The back emf in a DC motor is maximum when,

Motor has picked up maximum speed

Motor has just started moving

Speed of motor is still increasing

Motor has been switched off

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AAKASH INSTITUTE-ELECTROMAGNETIC INDUCTION-Assignment (SECTION - A)

A coil having 500 square loops each of side 10 cm is placed normal to ...
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The coefficient of mutual induction between two circuits is equal to t...
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The back emf in a DC motor is maximum when,
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If the radius of a coil is changing at the rate of 10^(-2) unit in a n...
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If a coil of 40 turns and area 4.0 cm^(2) is suddenly remove from a m...
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The core of transformer is laminated so that
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Two coil are placed close to each other. The mutual inductance of the ...
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A magnetic flux of 500 microweber passing through a 200 turn coil is r...
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A coil of area 0.1m^(2) has 500 tums. After placing the coil in a magn...
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Two circular coils have their centres at the same point. The mutual in...
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When a battery is connected across a series combination of self induct...
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In a uniform magneitc field of induced B a wire in the form of a semic...
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A metal conductor of length 1m rotates vertically about one of its end...
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A copper disc of radius 0.1 m is roated about its centre with 20 revol...
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Two coils of self-inductance 2mH and 8 mH are placed so close togethe...
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The equivalent quantity of mass in electricity is
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Dimensional formula of self-inductance is
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A time varying magnetic flux passing through a coil is given by phi=xt...
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A metalic ring is dropped down, keeping its plane perpendicular to a c...
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Lights of a car become dim when the starter is opereterd. Why?
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