Question

In the circuit shown, the heat produced in the 5 ohm resistor due to current flowing through it, is 10 calories per second. Then the heat generated in the 4 ohm resistor is:

(A) 1 calorie per sec

(B) 2 calorie per sec

(C) 4 calorie per sec

(D) 3 calorie per sec

Answer 1

The correct option (B) 2 calorie per sec

Explanation:

H = I2 Rt

(H/t) = I2R

for 5Ω, (H/t) = 10 cal

∴ 10 = I12 × 5

I1 = √2A

Now V = I1(5) = I2(4 + 6)

∴ 5I1 = 10I2

∴ I2 = (I1/2) = (√2/2) = (1/√2)A

Hence heat in 4Ω resistor per second = (H/t) = I22 R

= (1/√2)2 × 4 = 2 cal