There `60 W`, `120 V` light bulbs are connected across a `120 V` power source. If resistance of each bulb does not change with current then find out total power deliver to the three bulbs.

Options

A. `180 W`
B. `20 W`
C. `40 W`
D. `60 W`

Answer

C

Explanation

(c ) Here `R = (V^(2))/(P)`
Total power supplied
`= (V^(2))/(3//2R) = ((2)/(3)) ((V^(2))/(R )) = (2)/(3) xx 60 = 40 W`