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32 votes
A light bulb uses 40.0 W of power when connected to a 110 V (DC) outlet. If the same bulb is connected to a European 220 V outlet, how much power will the bulb use?​

User Umesh Maharshi
by
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2 Answers

15 votes
15 votes

Answer:

160

Step-by-step explanation:

Acellus

User Low
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2.6k points
9 votes
9 votes

If the bulb's resistance doesn't change, the power it uses is proportional to the square of the voltage. So doubling the voltage quadruples the power.

On 220 V, the bulb uses (4 • 40w)= 160 W.

It glows very brightly.

For a very short time.

Because it also gets very hot, and burns out.

After a few seconds, it uses zero watts.