The power dissipated in the circuit shown in the figure is 30 Watts. The value of R is-

Options

A. `20 Omega`
B. `15 Omega`
C. `10 Omega`
D. `30 Omega`

Answer

C

Explanation

`P = V^(2)/r_(eq)`
`rArr 30 = (10)^(2)/((5R)/(5 + R)) rArr 30 = (100(5 + R))/(5 R)`
`rArr 150 R = 500 + 100 R`
`rArr R = 500/50 = 10 Omega`