A bulb used in a car is rated 12 V , 48 W . find the energy consumed in one minute when the bulb is connected to 6 V battery?

1 Answer
Apr 29, 2018

The energy consumed is #720 J#

Explanation:

One of the formulas for power is #P = V^2/R#. Therefore we can find the bulb's resistance using

#R = V^2/P = ((12 V)^2)/(48 W) = 3 Omega#

If we use 6 V instead, the power consumption is #P' = ((6 V)^2)/(3 Omega) = 12 W = 12 J/s#.

In one minute, the energy consumed is #12 J/s*60 s = 720 J#

I hope this helps,
Steve