Question
Physics Question on Electromagnetic waves
A plane polarized monochromatic EM wave is traveling in vacuum along z direction such that at t=t1 it is found that the electric field is zero at a spatial point z1. The next zero that occurs in its neighbourhood is at z2. The frequency of the electromagnetic wave is :
A
∣z2−z1∣3×108
B
∣z2−z1∣1.5×108
C
∣z2−z1∣6×108
D
t1+3×108∣z2−z1∣1
Answer
∣z2−z1∣1.5×108
Explanation
Solution
The correct option is(B): ∣z2−z1∣1.5×108
Since c=fλ⇒f=λc.
Here, λ=2∣z2−z1∣ and c=3×108. Therefore,
f=2∣z2−z1∣3×108=∣z2−z1∣1.5×108