Current Electricity 5 Question 11
11. Figure shows three resistor configurations $R _1, R _2$ and $R _3$ connected to $3 V$ battery. If the power dissipated by the configuration $R _1, R _2$ and $R _3$ is $P _1, P _2$ and $P _3$, respectively, then
(2008, 3M)
(a) $P _1>P _2>P _3$
(b) $P _1>P _3>P _2$
(c) $P _2>P _1>P _3$
(d) $P _3>P _2>P _1$
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Solution:
- Applying $P=\frac{V^{2}}{R}, R _1=1 \Omega, R _2=0.5 \Omega$ and $R _3=2 \Omega$
$$ \begin{aligned} & V _1=V _2=V _3=3 V \\ \therefore & P _1=\frac{(3)^{2}}{1}=9 W \end{aligned} $$
$P _2=\frac{(3)^{2}}{0.5}=18 W$ and $P _3=\frac{(3)^{2}}{2}=4.5 W$
$\therefore \quad P _2>P _1>P _3$
$\therefore$ Correct option is (c).