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 by a coil is calculated using the formula \( P = I^2 R \). Here, \( P \) represents the dissipated power, \( I \) denotes the current, and \( R \) signifies the resistance. With \( I = 2 \, \text{A} \) and \( R = 10 \, \Omega \), the power is determined as follows: \[ P = (2)^2 \times 10 = 4 \times 10 = 40 \, \text{W} \] Consequently, the coil dissipates \( 40 \, \text{W} \) of power.