Moderate

An immersion heater of 400 watts kept on for 5 hours will consume electrical power of?

Correct answer: A. 2 kWh

  • A. 2 kWh
  • B. 20 kWh
  • C. 6 kWh
  • D. 12 kWh

Explanation

To calculate the electrical power consumed by the immersion heater, you can use the formula: Power (P) = Voltage (V) × Current (I) Given that the heater's power rating is 400 watts, and assuming it operates at the standard household voltage of 220 volts: Power (P) = 400 watts Voltage (V) = 220 volts Now, we need to calculate the current (I) using Ohm's Law: Current (I) = Power (P) / Voltage (V) Current (I) = 400 watts / 220 volts Once we have the current, we can calculate the total electrical energy consumed using the formula: Energy (E) = Power (P) × Time (t) Given that the heater is kept on for 5 hours: Energy (E) = 400 watts × 5 hours Now, plug in the values and calculate: Current (I) = 400 watts / 220 volts ≈ 1.818 Amperes Energy (E) = 400 watts × 5 hours = 2000 watt-hours (Wh) or 2 kilowatt-hours (kWh) So, the immersion heater will consume electrical power of 2 kilowatt-hours (kWh) when kept on for 5 hours.

Last updated

About Current Electricity

Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.

Practise Current Electricity

1,052 free Current Electricity MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Physics questions like this

Physics is on 15 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions