Question

Equivalent resistance between print x and y in the combination of resistance shown is

• A. $20\Omega$
• B. $18\Omega$
• C. $32\Omega$
• D. $40\Omega$

Answer 1

The correct option is C $32\Omega$

The equivalent resistance between B and y is $R_1=100||25=\frac{100\times 25}{100+25}=\frac{2500}{125}=20\Omega$

The equivalent resistance between A and y is $R_2=(100+R_1)||120=120||120=\frac{120\times 120}{120+120}=\frac{14400}{240}=60\Omega$

The equivalent resistance between x and y is $R_{xy}=(100+R_2)||40=160||40=\frac{160\times 40}{160+40}=\frac{6400}{200}=32\Omega$