Question
Obtain expression for root mean square value of alternating emf. Draw graph between $E$ and t and $E ^2$ and $t$ and prove that average rate of heat produced for alternating current in one complete cycle is $H = I _{\text {max }}^2 R$.
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→ Two blocks A and B, each of mass m, are placed on the two sides of the stand. At t = 0, the separation between A and the mirrors is 2 R and also the separation between B and the mirrors is 2 R. The block B moves towards the mirror at a speed v. All collisions which take place are elastic. Taking the original position of the mirrors-stand system to be x = 0 and X-axis along AB, find the position of the images of A and B at t = -
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