Question

An electric bulb is rated ${}^{\prime }100W,250V^{\prime }$. How much current will the bulb draw if connected to a $250V$ supply

• A. $0.6A$
• B. $2.5A$
• C. $5A$
• D. $0.4A$

Answer 1

The correct option is D $0.4A$

The electric power in watts associated with a complete electric circuit or a circuit component represents the rate at which energy is converted from the electrical energy of the moving charges to some other form, e.g., heat, mechanical energy, or energy stored in electric fields or magnetic fields.That is, $P=VI$ where, $Pe$ is the power in watts, $V$ is the voltage in volts and I is the current in amperes.

Therefore, if the power is 100 W and the supply voltage is 250 V, then the

current is $I=\frac{P}{I}=\frac{100W}{250V}=0.4A$.

Hence, the amount of current the bulb will draw is 0.4 amperes.