Q. In the circuit shown in figure, the heat produced by the 6$\ \Omega$ resistance is 60$\Omega$ $cal\ s^{- 1}$. What heat per second is produced across 3$\Omega$ resistance?
A) 30 cal
B) 60 cal
C) 100 cal
D) 120 cal
Explanation
(d) $I^{2} \times 6 = 60\ or\ I = \sqrt{10}$ A
Current through upper branch$\ = 2\sqrt{10}$A. Heat produced per second $3\Omega =$
$(2{\sqrt{10)}}^{2} \times 3$ cal = 120 cal.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.