Physics-
General
Easy
Question
A conducting rod of length 
is moved at constant velocity 
on two parallel, conducting, smooth, fixed rails, that are placed in a uniform constant magnetic field B perpendicular to the plane of the rails as shown in figure. A resistance R is connected between the two ends of the rail. Then which of the following is/are correct
- The thermal power dissipated in the resistor is equal to rate of work done by external person pulling the rod.
- If applied external force is doubled than a part of external power increases the velocity of rod.
- Lenz’s Law is not satisfied if the rod is accelerated by external force
- If resistance R is doubled then power required to maintain the constant velocity
becomes half.
becomes half.
The correct answer is: The thermal power dissipated in the resistor is equal to rate of work done by external person pulling the rod.
Rate of work done by external agent is :
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