NEET Electromagnetic Waves — Set 22

Question 1

What is the typical wavelength range of radio waves used in television communication?

Accepted Answer

The document mentions that TV waves range from $ 54 \, \text{MHz} $ to $ 890 \, \text{MHz} $. Using $ \lambda = \frac{c}{v} $, this corresponds to wavelengths from about $ 0.34 \, \text{m} $ to $ 5.56 \, \text{m} $. A simpler range based on frequency is used here.

Question 2

Why are X-rays used in crystallography to study atomic structures?

Accepted Answer

X-rays have wavelengths comparable to atomic spacings, allowing them to diffract off crystal lattices and produce interference patterns that reveal atomic arrangements.

Question 3

Why are gamma rays more hazardous than visible light when interacting with human tissue?

Accepted Answer

Gamma rays have much higher energy due to their extremely short wavelengths, enabling them to penetrate tissues and cause ionization, which damages cells, unlike visible light.

NEET Physics: Electromagnetic Waves — Practice Set 22

Q1. What is the typical wavelength range of radio waves used in television communication?

Q2. Why are X-rays used in crystallography to study atomic structures?

Q3. Why are gamma rays more hazardous than visible light when interacting with human tissue?

Q4. Which electromagnetic waves are used in remote switches of household electronic systems?

Q5. An electromagnetic wave has a magnetic field amplitude of \( B_0 = 6 \times 10^{-8} \, \text{T} \). What is the electric field amplitude? (Given \( c = 3 \times 10^8 \, \text{m/s} \))

Q6. An electromagnetic wave in vacuum has a frequency of \( 40 \, \text{MHz} \). What is its wavelength? (Given \( c = 3 \times 10^8 \, \text{m/s} \))

Q7. What distinguishes the mechanism of energy transfer in electromagnetic waves from that in mechanical waves?

Q8. What explains the ability of electromagnetic waves to exhibit polarization?

Q9. What makes electromagnetic waves different from other waves discussed in the document?

Q10. What is one precaution welders take to protect their eyes from UV radiation?