Electromagnetic Waves
Class 12 · Physics
Sample Questions
Q1.The displacement current formula is id = ε₀(dΦE/dt). If the electric flux through a surface between capacitor plates changes at a rate of 2 × 10¹² V·m/s, what is the displacement current? (ε₀ = 8.85 × 10⁻¹² C²/N·m²)
- A0.885 A
- B17.7 A
- C17.7 mA
- D8.85 A
Q2.A radar system uses microwaves with a wavelength of 3 cm. What is the frequency of these microwaves?
- A1 GHz
- B10 GHz
- C100 GHz
- D0.1 GHz
Q3.The amplitude of the magnetic field in an electromagnetic wave in vacuum is B₀ = 510 nT. What is the amplitude of the electric field?
- A153 N/C
- B153 V/m
- C1.7 × 10⁻¹⁶ V/m
- D1.7 V/m
Q4.Which layer of the atmosphere protects us from harmful ultraviolet radiation from the Sun?
- ATroposphere
- BStratosphere
- COzone layer
- DIonosphere
Q5.Which of the following electromagnetic waves has the highest frequency?
- ARadio waves
- BInfrared rays
- CVisible light
- DGamma rays
Q6.This is a sample question to preview what you'll get in the full practice test...
- A. Option one
- B. Option two
- C. Option three
- D. Option four
Concepts Covered
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