Physics-
General
Easy
Question
A short-circuited coil is placed in a time-varying magnetic field. Electrical power is dissipated due to the current induced in the coil. If the number of turns were to be quadrupled and the wire radius halved, the electrical power dissipated would be
- Halved
- The same
- Doubled
- Quadrupled
The correct answer is: The same
Sol. Power 
hence 
where 
Also 
Where R = resistance, r = radius, l = Length
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