Question

A coil of resistance 10 \( \Omega \) is connected to a battery of 12 V. If the current flowing through the coil is 2 A, what is the power dissipated in the coil?

• A. 40 W
• B. 10 W
• C. 24 W
• D. 30 W

Hint:

To find the power dissipated in a resistor, use the formula \( P = I^2 R \). If you know the voltage and resistance, you can also use \( P = \frac{V^2}{R} \) for easier calculation.

Answer 1

The Correct Option is A

The power dissipated in a coil is given by the formula: \[ P = I^2 R \] Where: - \( P \) is the power dissipated,
- \( I \) is the current,
- \( R \) is the resistance.
Given: - \( I = 2 \, \text{A} \),
- \( R = 10 \, \Omega \).
Substitute these values into the formula: \[ P = (2)^2 \times 10 = 4 \times 10 = 40 \, \text{W} \] Thus, the power dissipated in the coil is \( 40 \, \text{W} \).