621. Which law states that every action has an equal and opposite reaction — select the correct answer.
✅ A. Newton's third law
Newton's third law describes action and reaction forces. Read more
Physics – Page 32
622. What instrument measures potential difference — select the correct answer.
✅ D. Voltmeter
A voltmeter measures potential difference. Read more
623. What is the speed of light in vacuum approximately — select the correct answer.
✅ D. 3 × 10^8 m/s
Light travels in vacuum at approximately 3 × 10^8 meters per second. Read more
624. What is the SI unit of power — select the correct answer.
✅ D. Watt
Power is measured in watts. Read more