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aChordate
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One of my homework questions is giving me trouble:
"In, the US, the rms voltage from power outlets (known as line voltage) is 120 V. In the United Kingdom, line voltage is 230 V. If you take a lamp with a standard 100 W incandescent light bulb from the US, how much power will it dissipate if used in the UK? Assume that the electrical resistance of the bulb is constant."
So, I know that V=IR and P=VI. V1=120 V and V2= 230 V and the P of the light bulb= 100 W. Should I plug in power of the light bulb to the formula P=IV and find the current and then use that to find the excess power. For example,
P/V=I
(100W)/(120V)=I
I=0.8A
P=(0.8A)(230 V)= 200 W - 100 W = 100 W dissipated
I have no idea if I am on the right track or not, please help.
Thanks in advance.
"In, the US, the rms voltage from power outlets (known as line voltage) is 120 V. In the United Kingdom, line voltage is 230 V. If you take a lamp with a standard 100 W incandescent light bulb from the US, how much power will it dissipate if used in the UK? Assume that the electrical resistance of the bulb is constant."
So, I know that V=IR and P=VI. V1=120 V and V2= 230 V and the P of the light bulb= 100 W. Should I plug in power of the light bulb to the formula P=IV and find the current and then use that to find the excess power. For example,
P/V=I
(100W)/(120V)=I
I=0.8A
P=(0.8A)(230 V)= 200 W - 100 W = 100 W dissipated
I have no idea if I am on the right track or not, please help.
Thanks in advance.