Calculate Current Using Power and Resistance
This solution explains how to find the electric Current (I) when Power (P) and Resistance (R) are given.
Identify Given Values
- Power ($P$): 100 watts
- Resistance ($R$): 4 ohms
Relevant Formula
The relationship between Power ($P$), Current ($I$), and Resistance ($R$) is given by the formula:
$ P = I^2 \times R $
Derive Formula for Current
To find the Current ($I$), we need to rearrange the formula:
- Divide both sides by Resistance ($R$):
$ \frac{P}{R} = I^2 $
- Take the square root of both sides:
$ I = \sqrt{\frac{P}{R}} $
Calculate Current
Substitute the given values into the derived formula:
$ I = \sqrt{\frac{100 \, \text{W}}{4 \, \Omega}} $
$ I = \sqrt{25 \, \text{A}^2} $
$ I = 5 \, \text{A} $
Conclusion
The calculated Current ($I$) is 5 A.
Similar Questions
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Important Questions from Power in Electric Circuits
Two electric bulbs marked 25 W - 220 V and 100 W - 220 V are connected in series with 440 V supply. Which of the bulb will fuse?
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If these two bulbs are connected in series across a $220$ V supply, what will be the power consumed by the $100$ W bulb? - Three identical bulbs are connected in parallel to a battery of 6 V. If the current in the circuit is 0.6 A, the power dissipated by the battery is:
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