- #1

carnivalcougar

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## Homework Statement

Imagine that you have a box of 9V batteries and a box of flashlight bulbs labeled 1.5V/3W for operational voltage/power. What is the ohmic resistance of the bulbs? Can you turn on the 1.5V bulbs without burning them out by using the available 9V batteries?

## Homework Equations

P=ΔW/t=ΔVI=ΔV

^{2}/R=I

^{2}R

I = P/V

R = V/I

## The Attempt at a Solution

I in the bulbs will be 3W/1.5V which is 2A

R in the bulbs will be 1.5V/2A which is .75ohms

If you attach one of the bulbs to a 9V battery, the voltage drop will be = to IR which is (2A)(.75ohms) which is 1.5V. So using a 9V battery the bulb will only get 1.5V which will not cause the bulb to burn out. Is this correct?