The amount of work done in increasing the voltage across the plates of capacitor from 5 V to 10 V is W. The work done in increasing it from 10 V to 15 V will be

Options

A. 0.6 W
B. 1 W
C. 1.25 W
D. 1.67 W

Answer

D

Explanation

As we know that, work done
`=U_("final")-U_("initial")=(1)/(2)C(V_(2)^(2)-V_(1)^(2))`
When potential difference increases from 5 V to 10 V, then
`W=(1)/(2)C(10^(2)-5^(2))" …(i)"`
When potential difference increases from 10 V to 15 V, then
`W'=(1)/(2)C(15^(2)-10^(2))" ...(ii)"`
On solving Eqs. (i) and (ii), we get
W' = 1.67 W