Homework Help: physics

Posted by Amelia on Monday, May 14, 2012 at 9:13am.

The operating potential difference of a light bulb is 120 V. The power rating of the bulb is 105 W. Find the current in the bulb and the bulb's resistance.
Current
1 A
Resistance
2

I got 0.916 for A
and 115 for B but they are wrong

physics - Elena, Monday, May 14, 2012 at 3:12pm
P=I•U ,
I =P/U =105/120 =0.875 A
P =I²•R,
R=P/I² =105/120²=7.3•10^-3 Ω
physics - Amelia, Monday, May 14, 2012 at 10:14pm
the second answer is supposed to be in the hundreds
physics - Elena, Tuesday, May 15, 2012 at 10:41am
7.3•10^-3 = 0.0073

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