521. Which wave requires a material medium to travel — select the correct answer.
✅ A. Sound wave
Sound is a mechanical wave and requires a medium. Read more
Physics – Page 27
522. Which simple machine is a rigid bar pivoted about a fixed point — select the correct answer.
✅ B. Lever
A lever is a rigid bar that rotates around a fulcrum. Read more
523. What happens to the resistance of a metallic conductor generally when temperature increases — select the correct answer.
✅ D. It increases
For typical metals, electrical resistance increases as temperature rises. Read more
524. Which quantity is measured in joules — select the correct answer.
✅ C. Energy
The joule is the SI unit of energy and work. Read more
525. What is momentum equal to — select the correct answer.
✅ B. Mass × velocity
Linear momentum is p = mv. Read more
526. Which phenomenon explains the bending of light when it passes between media — select the correct answer.
✅ A. Refraction
Refraction is the change in direction of light due to a change in speed between media. Read more
527. Which phenomenon is the bouncing back of light from a surface — select the correct answer.
✅ A. Reflection
Reflection is the return of light from a surface. Read more
528. What is the unit of magnetic flux density — select the correct answer.
✅ D. Tesla
Magnetic flux density is measured in teslas. Read more
529. What is frequency measured in — select the correct answer.
✅ B. Hertz
Frequency is measured in hertz. Read more
530. Which form of energy is stored in a stretched spring — select the correct answer.
✅ B. Elastic potential energy
A stretched spring stores elastic potential energy. Read more
531. What type of lens is thicker in the middle than at the edges — select the correct answer.
✅ B. Convex lens
A convex lens is thicker at the center and converges parallel light rays. Read more
532. What is the formula for kinetic energy — select the correct answer.
✅ A. ½mv²
Kinetic energy is one-half mass times velocity squared. Read more
533. 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
534. What is the unit of electrical resistance — select the correct answer.
✅ D. Ohm
Electrical resistance is measured in ohms. Read more
535. What is the acceleration due to gravity near Earth’s surface approximately — select the correct answer.
✅ A. 9.8 m/s²
Near Earth's surface, gravitational acceleration is approximately 9.8 m/s². Read more
536. What instrument measures electric current — select the correct answer.
✅ B. Ammeter
An ammeter measures electric current. Read more
537. What instrument measures potential difference — select the correct answer.
✅ D. Voltmeter
A voltmeter measures potential difference. Read more
538. 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
539. What is the SI unit of power — select the correct answer.
✅ D. Watt
Power is measured in watts. Read more
540. What is the SI unit of pressure — select the correct answer.
✅ B. Pascal
Pressure is measured in pascals. Read more