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
P=I•U ,
I =P/U =105/120 =0.875 A
P =I²•R,
R=P/I² =105/120²=7.3•10^-3 Ω
the second answer is supposed to be in the hundreds
7.3•10^-3 = 0.0073
To find the current in the bulb, you can use Ohm's Law, which states that the current flowing through a conductor is equal to the voltage across it divided by its resistance.
Given:
Operating potential difference (V) = 120 V
Power rating (P) = 105 W
To find the current (I), we can use the formula:
P = IV
From the formula, we can rearrange it to solve for the current (I):
I = P/V
Substituting the given values:
I = 105 W / 120 V
Calculating this expression will give us the value of the current flowing through the light bulb.
Now, to find the resistance (R) of the bulb, we can use another formula derived from Ohm's Law:
R = V/I
Substituting the given values:
R = 120 V / (calculated current)
By calculating this expression, we can determine the resistance of the light bulb.
Please note that we will need to use the exact numbers in the calculations to get the correct answers.