Question

A 9-volt battery is used to power 2 lightbulbs on separate branches of a parallel circuit. The first lightbulb has a resistance of 3 ohms and the second has a resistance of 2 ohms.

What is the power output of the battery?

Please show work if possible!

Answer 1

Power= current x potential difference

To find total resistors in ohms, in parallel circuit, do 1/given ohms for all resistors first; then, add them together:

1/3 ohms + 1/2 ohms = 5/6 ohms

V= IR

xR

VR = I

I=VR

= 9 x 5/6

= 7.5 amps

P = I x V

= 7.5 x 9

= 67.5

Hope this helps!