NEET Electromagnetic Waves — Set 6

Question 1

What enables electromagnetic waves to propagate through vacuum without a medium?

Accepted Answer

The document states that electromagnetic waves are self-sustaining oscillations of electric and magnetic fields, requiring no material medium for propagation.

Question 2

Why are UV lamps used in LASIK eye surgery?

Accepted Answer

The document mentions that due to their shorter wavelengths, UV rays can be focused into narrow beams, making them suitable for high-precision applications like LASIK eye surgery.

Question 3

What does Maxwell's introduction of displacement current explain in the context of a charging capacitor?

Accepted Answer

The document explains that displacement current accounts for the magnetic field between the plates of a charging capacitor, where there is no conduction current, ensuring consistency with Ampere's law.

NEET Physics: Electromagnetic Waves — Practice Set 6

Q1. What enables electromagnetic waves to propagate through vacuum without a medium?

Q2. Why are UV lamps used in LASIK eye surgery?

Q3. What does Maxwell's introduction of displacement current explain in the context of a charging capacitor?

Q4. What property of electromagnetic waves explains their ability to travel at the same speed in vacuum regardless of their frequency?

Q5. An electromagnetic wave has an angular frequency \( \omega = 8 \times 10^{11} \, \text{rad/s} \). What is its frequency in Hz?

Q6. An electromagnetic wave has a wave number \( k = 4 \, \text{rad/m} \). What is its wavelength in vacuum?

Q7. An electromagnetic wave has a wavelength of \( 3 \, \text{m} \) in vacuum. What is its wave number \( k \)?

Q8. What does Gauss's Law for electricity state in Maxwell's equations?

Q9. In electromagnetic theory, what explains the ability of waves to exhibit coherence?

Q10. Why are electromagnetic waves classified into different types in the spectrum?