A wire has a resistance of 4 ohm and carries a current of 3 A. What is the potential difference across it?
Answer and explanation
Correct answer: D. 12 V
- Step 1: Ohm's law gives V. Answer: 12 V. Why not the others: 0.75 V, 7 V and 1.33 V don't fit.
Practise more Physics: motion, force and energy.
Free questions with an explanation for every one, and full timed SEE (Secondary Education Examination, Nepal) mock tests.
More Physics: motion, force and energy questions
- A car moving at 20 m/s brakes uniformly and stops in 5 s. What is its deceleration?
- A force of 30 N acts on a body of mass 6 kg on a smooth surface. What acceleration does it produce?
- A stone of mass 2 kg is lifted 5 m above the ground. Taking m/s², what potential energy does it gain?
- A bulb rated 60 W is switched on for 5 hours. How many units (kWh) of electrical energy does it use?
- Two resistors of 6 ohm and 3 ohm are joined in parallel. What is their combined resistance?
- Which instrument is used to measure the strength of an electric current?