When a Coolidge tube is operated for some time it becomes hot. Where does the heat come from?

A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of 50 rad s^(-1) in a uniform horizontal magnetic field of magnitude 3.0 xx 10^(-2) T. Obtain the maximum and average emf induced in the coil. If the coil forms a closed loop of resistance 10 Omega , calculate the maximum value of current in the coil. Calculate the average power loss due to Joule heating. Where does this power come from ?

When does the average velocity become zero?

When does the magnetic flux becomes zero ?

Assertion: Current is passed through a metallic wire, heating it red. When cold water is poured on half of its portion, then rest of the half portion become more hot. Reason: Resistance decreases due to decrease in tem perature and so current through wire increases.

A manufacturer has three machine operators A, B and C. The first operator A produces 1% defective items, where as the other two operators B and C produce 5% and 7% defective items respectively. A is on the job for 50% of the time, B is on the job for 30% of the time and C is on the job for 20% of the time. A defective item is produced, what is the probability that it was produced by A?

Fallopian tubes come out from the vas deferens.

A cup contains some mercury in it. Now a narrow glass tube is lowered in the mercury. After some time the mercury level in the tube becomes lower than the mercury level outside the tube as shown in diagram. During this process (Choose correct statements)