NEET Electromagnetic Waves — Set 9

Question 1

What type of electromagnetic waves did Maxwell predict before their experimental discovery?

Accepted Answer

The document mentions that Maxwell predicted the existence of electromagnetic waves, which were later confirmed to include light, radio waves, and others, but initially, they were general EM waves.

Question 2

What inconsistency did Maxwell notice in Ampere's circuital law before introducing displacement current?

Accepted Answer

Maxwell noticed that Ampere's law gave different results for the magnetic field outside a capacitor depending on the surface used, leading to a contradiction when calculating the field at a point.

Question 3

What is the wavelength of an electromagnetic wave in vacuum with frequency $ 50 \, \text{MHz} $? (Given $ c = 3 \times 10^8 \, \text{m/s} $)

Accepted Answer

Using $ v \lambda = c $, we have $ \lambda = \frac{c}{v} = \frac{3 \times 10^8}{50 \times 10^6} = 6 \, \text{m} $.

NEET Physics: Electromagnetic Waves — Practice Set 9

Q1. What type of electromagnetic waves did Maxwell predict before their experimental discovery?

Q2. What inconsistency did Maxwell notice in Ampere's circuital law before introducing displacement current?

Q3. What is the wavelength of an electromagnetic wave in vacuum with frequency \( 50 \, \text{MHz} \)? (Given \( c = 3 \times 10^8 \, \text{m/s} \))

Q4. Why are ultraviolet lamps used in water purifiers?

Q5. According to Maxwell's equations, what does the equation \( \oint \mathbf{B} \cdot \mathrm{d} \mathbf{A} = 0 \) imply?

Q6. What is the approximate wavelength range of visible light?

Q7. What is the approximate wavelength range of radio waves as per the document?

Q8. An electromagnetic wave in vacuum has an electric field given by \( E_x = 150 \sin(5 \times 10^3 z - 1.5 \times 10^{12} t) \, \text{V/m} \). What is the angular frequency \( \omega \)?

Q9. Why are infrared detectors used in Earth satellites?

Q10. Why are infrared waves used in remote switches of household electronic systems?