Question

A set of three identical resistors $R$ are wired to a to a $10V$ battery as shown in the circuit diagram below.If the current leaving the battery is 1 amp, what is the power dissipated by each resistor?

• A. $\frac{1}{10}W$
• B. $10W$
• C. $\frac{3}{100}W$
• D. $\frac{100}{3}W$
• E. $\frac{10}{3}W$

Answer 1

Answer: (E)

$\frac{10}{3}W$

Given : $V=10$ volts $I=1$ amp

Equivalent resistance of the circuit $\frac{1}{R_{eq}}=\frac{1}{R}+\frac{1}{R}+\frac{1}{R}$ $⟹R_{eq}=\frac{R}{3}$

Using Ohms law : $V=I{R}_{eq}$

$\therefore$ $10=1\times \frac{R}{3}$ $⟹R=30$ ohms

Thus power dissipated in each resistor $P=\frac{V^2}{R}=\frac{(10{)}^2}{30}=\frac{10}{3}$ Watts