Two resistors are connected in parallel, whose resistance values are in the ratio 3:1. Find the ratio of power dissipated.(a) 1:3(b) 3:1(c) 1:2(d) 2:1I got this question in a national level competition.Query is from Combination of Resistors topic in chapter Current Electricity of Physics – Class 12

Two resistors are connected in parallel, whose resistance values are i

1.	Two resistors are connected in parallel, whose resistance values are in the ratio 3:1. Find the ratio of power dissipated.(a) 1:3(b) 3:1(c) 1:2(d) 2:1I got this question in a national level competition.Query is from Combination of Resistors topic in chapter Current Electricity of Physics – Class 12
Answer» Right CHOICE is (a) 1:3 For explanation: We can consider the relation that INCLUDES power and RESISTANCE, i.e.Power = \(\frac {voltage^2}{resistance}\). SINCE, the resistors are connected in parallel, the voltage across them will be the same. From this relation, power and resistance are inversely proportional to each other. Thus, \(\frac {P1}{P2} = \frac {R2}{R1} = \frac {1}{3}\) So, the power dissipated is in the RATIO is 1:3.

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