Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Electromagnetic Waves

Question:

A plane electromagnetic wave of frequency 40 MHz travels in free space in the X-direction. At some point and at some instant, the electric field $\vec{E}$ has its maximum value of 750 N/C in Y-direction. The wavelength of the wave is:

Options:

3.5 m

5.5 m

7.5 m

9.5 m

Correct Answer:

7.5 m

Explanation:

$\lambda=\frac{C}{f}=\frac{3 \times 10^8}{4 \times 10^7}$ = 7.5 m