Question

A resistor with resistance R carries a sinusoidally varying AC. Obtain an expression for the heat produced in the resistor in one complete cycle.​

Answer 1

Answer:

(a) when an electric charge Q moves against a p.d. V, the amount of work done is

W = Q × V ------(1)

We know, current, I = Q/t

Q = I × t -------(2)

By ohm’s law, (V/I) = R

V = I × R -----(3)

Putting eqs. (2) and (3) in eq, (1),

W = I × t × I × R

W = I²Assuming that all the electrical work done is converted into heat energy, we get

Heat produced, H = I2Rt joules

This relation is known as joule’s law of heating.

(b) Given: P = 12W, V = 12V, t = 60sec

P = VI

I = P/V = 12/12 = 1A

V = IR

R = V/I = 12/1 = 12ohmRt

H = I2Rt

H = 12 x 12 x 60

H = 720J

Answer 2

Answer:

nice

Explanation: