Question

Three resistances of equal values are arranged in four different configurations as shown below. Power dissipation in the increasing order is

• A. $(III)<(II)<(IV)<(I)$
• B. $(II)<(III)<(IV)<(I)$
• C. $(I)<(IV)<(III)<(II)$
• D. $(I)<(III)<(II)<(IV)$

Answer 1

Answer: (A)

For figure I,
Total resistance $=3R$
I power $=I^2(3R)$
For figure II,
Resistance $=\frac{2R}{3}\Omega$
II power $=I^2\left(\frac{2R}{3}\right)$
For figure III,
Total resistance $=\frac{R}{3}\Omega$
III power $=I^2\left(\frac{R}{3}\right)$
For figure IV,
Total resistance $\frac{3}{2}\Omega$
IV power $=I^2\left(\frac{3}{2}R\right)$