Electromagnetic Waves  MCQs

MCQs of Electromagnetic Waves

Showing 31 to 40 out of 112 Questions
31.
Heat radiation is propogating with the velocity of _____
(a) α - rays
(b) β - rays
(c) rays of light
(d) sound waves
Answer:

Option (c)

32.
In Hertz experiment rods act as
(a) inductor
(b) solenoid
(c) capacitor
(d) none of above
Answer:

Option (a)

33.
The magnitude of radiated components in Hertz experiments decreases with distance (r) as _____
(a) 1r
(b) r
(c) 1r2
(d) 1r3
Answer:

Option (a)

34.
If magnitude of inductive component of electromagnetic waves is E and the distance from its source is r then E∝ _____
(a) 1r
(b) 1r3
(c) 1r2
(d) r
Answer:

Option (b)

35.
For the electromagnetic waves propagating in the X - direction, oscillation of E takes places along y - axis. What from the following is right ?
(a) Ex = Ey = 0, Ez ≠ 0
(b) Ex = Ez = 0, Ey ≠ 0
(c) Ex ≠ Ey, Ez ≠ 0
(d) Ex = Ey = Ez
Answer:

Option (b)

36.
The energy of some part of the electromagnetic waves is U and momentum of this part is P then,
(a) P = Uc
(b) P = Uc
(c) P = Uc2
(d) P = U2c
Answer:

Option (b)

37.
Which of the following rays are not electromagnetic waves ?
(a) X - rays
(b) γ - rays
(c) β - rays
(d) Heat rays
Answer:

Option (c)

38.
What is the uppermost layer of the atmosphere called ?
(a) Inosphere
(b) Mesosphere
(c) Stratosphere
(d) Troposphere
Answer:

Option (a)

39.
Give the name of the device from which visible light is produced.
(a) Klystrons
(b) Magnetron
(c) Gun diode
(d) Incandescent lamp
Answer:

Option (d)

40.
Who was the first scientist to demonstrate the existence of electromagnetic wave in the laboratory ?
(a) Hertz
(b) Faraday
(c) Maxwell
(d) Gauss
Answer:

Option (c)

Showing 31 to 40 out of 112 Questions