21. Select the best answer: Which simple machine is a rigid bar pivoted about a fixed point?
✅ B. Lever
A lever is a rigid bar that rotates around a fulcrum. Read more
Physics – Page 2
22. Select the best answer: What is momentum equal to?
✅ A. Mass × velocity
Linear momentum is p = mv. Read more
23. Select the best answer: Which phenomenon explains the bending of light when it passes between media?
✅ D. Refraction
Refraction is the change in direction of light due to a change in speed between media. Read more
24. Select the best answer: What is frequency measured in?
✅ B. Hertz
Frequency is measured in hertz. Read more
25. Select the best answer: What type of lens is thicker in the middle than at the edges?
✅ B. Convex lens
A convex lens is thicker at the center and converges parallel light rays. Read more
26. Select the best answer: What is the unit of electrical resistance?
✅ D. Ohm
Electrical resistance is measured in ohms. Read more
27. Select the best answer: What is the acceleration due to gravity near Earth’s surface approximately?
✅ D. 9.8 m/s²
Near Earth's surface, gravitational acceleration is approximately 9.8 m/s². Read more
28. Select the best answer: What instrument measures electric current?
✅ A. Ammeter
An ammeter measures electric current. Read more
29. Select the best answer: What is the SI unit of pressure?
✅ D. Pascal
Pressure is measured in pascals. Read more
30. Which of the following is correct? What happens to the resistance of a metallic conductor generally when temperature increases?
✅ C. It increases
For typical metals, electrical resistance increases as temperature rises. Read more
31. Which of the following is correct? Which quantity is measured in joules?
✅ C. Energy
The joule is the SI unit of energy and work. Read more
32. Which of the following is correct? Which phenomenon is the bouncing back of light from a surface?
✅ D. Reflection
Reflection is the return of light from a surface. Read more
33. Which of the following is correct? What is the unit of magnetic flux density?
✅ C. Tesla
Magnetic flux density is measured in teslas. Read more
34. Which of the following is correct? What type of lens is thicker in the middle than at the edges?
✅ A. Convex lens
A convex lens is thicker at the center and converges parallel light rays. Read more
35. Which of the following is correct? Which law states that every action has an equal and opposite reaction?
✅ B. Newton's third law
Newton's third law describes action and reaction forces. Read more
36. Which of the following is correct? What instrument measures potential difference?
✅ C. Voltmeter
A voltmeter measures potential difference. Read more
37. Which of the following is correct? What is the speed of light in vacuum approximately?
✅ D. 3 × 10^8 m/s
Light travels in vacuum at approximately 3 × 10^8 meters per second. Read more
38. Choose the correct answer. What happens to the resistance of a metallic conductor generally when temperature increases?
✅ B. It increases
For typical metals, electrical resistance increases as temperature rises. Read more
39. Choose the correct answer. Which quantity is measured in joules?
✅ A. Energy
The joule is the SI unit of energy and work. Read more
40. Choose the correct answer. Which phenomenon is the bouncing back of light from a surface?
✅ C. Reflection
Reflection is the return of light from a surface. Read more