Resistor 1 has twice the resistance of resistor 2.The two are connected in series and a potential difference is maintained across the combination.The rate of thermal energy dissipation in 1 is:
A)the same as that in 2
B)twice that in 2
C)half that in 2
D)four times that in 2
E)one fourth that in 2

Question

Quizplus · Accepted Answer

The rate of thermal energy dissipation (power) in a resistor is given by $P = I^2R$, where $I$ is the current through the resistor and $R$ is its resistance. In a series circuit, the current through each resistor is the same. Since Resistor 1 has twice the resistance of Resistor 2 ($R_1 = 2R_2$), the power dissipated in Resistor 1 is $P_1 = I^2(2R_2) = 2I^2R_2$, which is twice the power dissipated in Resistor 2 ($P_2 = I^2R_2$).

Resistor 1 Has Twice the Resistance of Resistor 2