Question

A direct current of 4 A and an alternating current of peak value 4 A flow through resistance of 3 Ω and 2 Ω respectively. The ratio of heat produced in the two resistances in same interval of time will be :

• A. 3 : 2
• B. 3 : 1
• C. 3 : 4
• D. 4 : 3

Answer 1

Answer: (B)

3 : 1

Answer 2

The correct answer is (B) : 3 : 1
Ratio$\frac{i_{1}^{2} R_1}{\left(\frac{i_2}{\sqrt{2}}\right)^2 R_2}$
$=\frac{4^2×3}{(\frac{4}{\sqrt{2}})^2×2}$
$⇒Ratio=3:1$