Physics-
General
Easy
Question
A galvanometer has an internal resistance of 
and current required for full scale deflection is 1 mA. Find the series resistances required as shown in fig, to use it as a voltmeter with different ranges, as indicated in fig.
The correct answer is:
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. if the switch S is closed. Will this lead to change in the reading of an ammeter.
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A rectangular coil PQ has 2n turns, an area 2a and carries a current 2I, (refer figure). The plane of the coil is at 60° to a horizontal uniform magnetic field of flux density B. The torque on the coil due to magnetic force is
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A particle with charge +Q and mass m enters a magnetic field of magnitude B, existing only to the right of the boundary YZ. The direction of the motion of the particle is perpendicular to the direction of B. Let 
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