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Which of the following statements is false for the properties of electromagnetic waves?
A
These waves do not require any material medium for propagation
B
Both electric and magnetic field vectors attain the maxima and minima at the same place and same time
C
The energy in electromagnetic wave is divided equally between electric and magnetic vectors
D
Both electric and magnetic field vectors are parallel to each other and perpendicular to the direction of propagation of wave
Detailed Solution
Electromagnetic waves can travel through vacuum; they need no material medium (true).
$\vec{E}$ and $\vec{B}$ oscillate in phase, so they reach their maxima and minima at the same place and time (true).
The average energy densities of the electric and magnetic fields are equal: $\frac{1}{2}\varepsilon_0E^2 = \frac{B^2}{2\mu_0}$ (true).
$\vec{E}$ and $\vec{B}$ are perpendicular to each other, and both are perpendicular to the direction of propagation; they are not parallel to each other.
Hence the false statement is that the electric and magnetic field vectors are parallel to each other.
$\vec{E}$ and $\vec{B}$ oscillate in phase, so they reach their maxima and minima at the same place and time (true).
The average energy densities of the electric and magnetic fields are equal: $\frac{1}{2}\varepsilon_0E^2 = \frac{B^2}{2\mu_0}$ (true).
$\vec{E}$ and $\vec{B}$ are perpendicular to each other, and both are perpendicular to the direction of propagation; they are not parallel to each other.
Hence the false statement is that the electric and magnetic field vectors are parallel to each other.