Question

heat produced in 5 ohm resistor is 10 cal/s. the heat generated in 4 ohm resistor is:​

Answer 1

answer : 2 Cal/s

explanation : in figure, it is clearly shown that (4Ω + 6Ω) and 5Ω are joined in parallel combination. and we know, potential difference across the parallel combination remains constant.

 so, we have to use formula of heat dissipated by resistor in a circuit, E = V²t/R

here, V and t are constant then, heat dissipated by resistor is inversely proportional to resistance .

or, H₁/H₂ = R₂/R₁

here, H₁ = 10cal/s , H₂ = ? , R₁ = 5Ω and R₂ = 4Ω + 6Ω = 10Ω

so, 10Cal/s/H₂ = 10Ω/5Ω = 2

so, H₂ = 5cal/s , this is the heat dissipated by (4Ω + 6Ω)

as, 4Ω and 6Ω are in series combination A and we know in series combination, current through the circuit always remains constant. so we should apply formula of heat dissipated by resistor in series combination is H = i²Rt

here i and t are constant terms so, heat is directly proportional to resistance.

or, H₂/H' = R₂/R'

here, R' = 4Ω , R₂ = 10Ω , H₂ = 5Cal/s

so, H' = 5(4/10) Cal/s = 2Cal/s