In the circuit shown below, the switch is in position 1 for a long time. At some moment after that the switch is thrown in position 2. The quantity of heat generated in the resistance of 375 ohm after the switch is changes to position 2 is :

Options

A. 0.15 J
B. 0.25 J
C. 0.50 J
D. 0.10 J

Answer

A

Explanation

`U=(1)/(2) 8 xx10^(-6) xx(250)^(2)`
`=4xx25 xx25 xx10^(-4)=0.25 J`
`U_(375 Omega)=(0.25 xx 375)/(375 +250)=0.15 J`