Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Electromagnetic Waves question

2013 · Shift 0 · Q52
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Electromagnetic Waves
  5. /2013 · Shift 0 · Q52

Electromagnetic Waves question

2013 · Shift 0 · Q52

JEE MainPhysicsElectromagnetic WavesMCQ+4 / −1
The magnetic field in a travelling electromagnetic wave has a peak value of 20nT20nT20nT. The peak value of electric field strength is :
  1. A
    3V/m3V/m3V/m
  2. B
    6V/m6V/m6V/m
  3. C
    9V/m9V/m9V/m
  4. D
    12V/m12V/m12V/m
View written solutionFree

Correct answer: B

  1. For an electromagnetic wave travelling in free space, the electric and magnetic field amplitudes are related by

E0=cB0E_0 = c B_0E0​=cB0​

where:

  • E0E_0E0​ = peak electric field
  • B0B_0B0​ = peak magnetic field
  • c=3×108 m/sc = 3 \times 10^8\ \text{m/s}c=3×108 m/s
  1. Given:

B0=20 nT=20×10−9 TB_0 = 20\ \text{nT} = 20 \times 10^{-9}\ \text{T}B0​=20 nT=20×10−9 T

  1. Now calculate E0E_0E0​:

E0=cB0=(3×108)(20×10−9)E_0 = cB_0 = (3 \times 10^8)(20 \times 10^{-9})E0​=cB0​=(3×108)(20×10−9)

E0=60×10−1=6 V/mE_0 = 60 \times 10^{-1} = 6\ \text{V/m}E0​=60×10−1=6 V/m

  1. Therefore, the peak electric field is

6 V/m\boxed{6\ \text{V/m}}6 V/m​

  1. Checking options:
  • A: 3 V/m3\ \text{V/m}3 V/m — incorrect
  • B: 6 V/m6\ \text{V/m}6 V/m — correct
  • C: 9 V/m9\ \text{V/m}9 V/m — incorrect
  • D: 12 V/m12\ \text{V/m}12 V/m — incorrect
PreviousNext

More from Electromagnetic Waves

  • An electromagnetic wave in vacuum has the electric and magnetic field E→​ and B→​, which are always perpendicular to each other. The direction of polarization is given by X→​ and…2012 · MCQ
  • The rms value of the electric field of the light coming from the Sun is 720N/C. The average total energy density of the electromagnetic wave is2006 · MCQ
  • An electromagnetic wave of frequency v=3.0MHz passes from vacuum into a dielectric medium with permittivity ∈=4.0. Then2004 · MCQ
  • A radiation of energy E falls normally on a perfectly reflecting surface. The momentum transferred to the surface is2004 · MCQ
  • Which of the following are not electromagnetic waves?2002 · MCQ
  • Electromagnetic waves are transverse in nature is evident by2002 · MCQ
  • The unit of ε0​c2I​​ is : (I = intensity of an electromagnetic wave, c = speed of light)2025 · MCQ
  • A parallel plate capacitor of area A=16 cm2 and separation between the plates 10 cm , is charged by a DC current. Consider a hypothetical plane surface of area A0​=3.2 cm2 inside the capacitor and…2025 · Numerical