The ratio of heat dissipated per second through the resistance 5Ω and 10Ω in the circuit given below is :
(A)1:2
(B)2:1✓ Correct
(C)4:1
(D)1:1
Answer: (B)
Solution
The 5Ω and 10Ω resistors share the same voltage (they are the two parallel branches), so the current divides inversely with resistance: i2i1=510=2, where i1 flows through the 5Ω branch. Power dissipated P=i2R, so
P2P1=(i2i1)2×R2R1=(2)2×105=4×21=2
The ratio of heat dissipated is 2:1.
JEE Main · 2024 · 05 Apr 2024 · Shift 2 · Single correct option