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Define electric power. When… (Class 10 Science 2025, Q25b)

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ScienceCBSE Class 10 · Board exam 2025, set 31/1/1 · 2 marks · Very short answer

CBSE Class 10 Science 2025: question 25(b)

Set in the CBSE Class 10 board exam of 2025, paper 31/1/1, section B, question 25(b), for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q25(b) · 2 marks · Very short answerElectricity

Define electric power. When do we say that the power consumed in an electric circuit is 1 watt?

Source: official question paper from cbse.gov.in (PDF). See it in the full 2025 board paper, set 31/1/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Power always means the rate of doing something with energy.

Hint 2

Use and put in the unit values of and .

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Electric power is the rate at which electrical energy is consumed or dissipated in a circuit, that is, electrical energy used per unit time: .

    1 mark

  2. Since , the power consumed is 1 watt when a current of 1 ampere flows through a circuit across a potential difference of 1 volt. Equivalently, 1 joule of electrical energy is consumed in 1 second: .

    1 mark

Answer: Power = rate of consumption of electrical energy; 1 W when 1 A flows under 1 V (1 J consumed per second)

Where the marks are

  • Defines electric power as the rate of consumption or dissipation of electrical energy (1 mark)
  • States 1 W as 1 A flowing at 1 V p.d., or 1 J consumed in 1 s (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Electricity, one at a time, marked against the answer key and marking points.Back to the full paper2025 board paper, set 31/1/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.