Electromagnetic Waves Mock Test – Class 12 Physics

1. A plane electromagnetic wave is written as and . The wave propagates along

2. The expression shows that the speed of electromagnetic waves in vacuum depends on

3. Study the table and select the row that correctly connects an electromagnetic region with a common source or use.

4. Assertion: The mutual connection between changing electric and magnetic fields helps explain electromagnetic waves.
Reason: A changing electric field can produce a magnetic field, and a changing magnetic field can produce an electric field.

5. A plane electromagnetic wave has , , and both fields are in phase. The wave propagates along

6. A claim says, "If ozone absorbs ultraviolet radiation, then no ultraviolet radiation can ever reach Earth's surface." The claim is

7. Microwaves lie in the electromagnetic spectrum between

8. A radio signal from a distant transmitter is received clearly over a large region. One suitable atmospheric reason is that

9. A student writes a wave-direction note as , , and propagation along . The note should be corrected because

10. A plane region in space has a time-varying electric field. According to the Maxwell-correction idea, the immediate magnetic-field-related effect is that the changing electric field can

11. A compact passage says:

The last sentence of the passage describes

12. The energy density stored in an electric field of magnitude in vacuum is

13. A radiation has short wavelength, high photon energy, strong penetration, and requires careful shielding in medical use. It is most likely

14. Match the basic field symbols with their usual meanings.

15. A law summary is written as: "A changing magnetic flux is associated with an induced electric field." The law being described is

16. X-rays are useful in studying crystal structure because their wavelengths are often

17. Assertion: Electromagnetic waves can travel through vacuum.
Reason: Their propagation is associated with time-varying electric and magnetic fields, not with vibrations of material particles.

18. A basic wave record for an electromagnetic wave lists , , and . The blank in the relation is best filled by

19. Visible light belongs to the family of

20. The basic relation connecting speed , frequency , and wavelength of an electromagnetic wave in vacuum is

21. Gauss's law for magnetism is commonly summarized by saying that

22. Study the table and identify the row that correctly states the vacuum-speed idea.

23. Ozone in the upper atmosphere is important because it absorbs much of the harmful part of

24. A communication engineer avoids a frequency band that is strongly absorbed by atmospheric molecules. The reason is that strong absorption would

25. A displacement current and a conduction current are compared only by their SI units. The suitable unit for both is

26. An electromagnetic wave is best described as a wave made of

27. Ultraviolet radiation is commonly associated with

28. A changing magnetic field is known to induce an electric field. Maxwell's correction completes the reciprocal idea by saying that

29. A plane electromagnetic wave in vacuum is represented by . The corresponding magnetic field amplitude is

30. A beam is reflected normally from a shiny surface instead of being absorbed by a black surface. For the same incident electromagnetic beam, the radiation pressure is larger on the shiny surface because

31. In the corrected Ampere-Maxwell law, the expression represents

32. Study the safety classification table and choose the most suitable row.

33. Study the table and select the row that is physically consistent.

34. In a table of Maxwell-equation meanings, the entry "net magnetic flux through a closed surface" should be paired with

35. Radio waves are commonly produced in communication systems by

36. In a plane electromagnetic wave travelling through free space, the electric field , magnetic field , and direction of propagation are arranged so that

37. A plate of a capacitor receives charge at a steady rate so that increases uniformly with time. In the ideal parallel-plate region, the graph of electric flux versus charge should be

38. Use the arrangement described below. A circular loop is drawn around the wire leading to a charging capacitor. Surface P is a flat surface cutting the wire. Surface Q has the same boundary loop but bulges between the capacitor plates. In the original Ampere-law view, Surface P and Surface Q create a problem because

39. A plane electromagnetic wave has . For the wave to propagate along , the magnetic field component should be

40. Radiation pressure is possible because electromagnetic waves carry

41. A capacitor is being charged, and a surface through the plate gap has but . Another surface with the same boundary cuts the wire. Under ideal conditions, the wire surface should have

42. A radio transmitting antenna works because charges in it are made to

43. Consider the following statements about electromagnetic-wave propagation.
Statement I: The wave can travel through vacuum.
Statement II: The wave carries energy in its electric and magnetic fields.
Statement III: The wave requires a material medium because it is a mechanical vibration.

44. A microwave signal has frequency . Its wavelength in vacuum is

45. Match the quantities with their physical roles.

46. In vacuum, an electromagnetic wave with frequency has wavelength

47. Electromagnetic waves transport energy from one region to another mainly through

48. If two electromagnetic waves travel in vacuum and wave P has a shorter wavelength than wave Q, then wave P has

49. Faraday's law and Maxwell's correction show a useful symmetry between fields. The paired idea is that a changing magnetic field produces an electric field, while

50. A region of the atmosphere is transparent to visible light but absorbs much of a neighbouring higher-frequency solar radiation. The absorbed neighbouring radiation is most likely