Moderate

Calculate the work done in a resistor of 20 ohms carrying 5A of current in 3 hours.

Correct answer: B. 1.5 kWh

  • A. 1 kWh
  • B. 1.5 kWh
  • C. 2 kWh
  • D. 3 kWh

Explanation

Work done is equal to energy which is power divided by timeE=P x tP =I2 x R = 52 x 20 = 500 WE = 500 x 3 = 1500 J1500 J = 1.5kWh

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 13 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