NEET Physics Question - Electromagnetic Waves

**Assertion (A):** The energy in a small volume through which an EM wave is passing oscillates with double the frequency of wave.

**Reason (R):** The electric field and magnetic field can not have equal average numerical value in each half cycle.

Both (A) &(R) are true and the (R) is the correct explanation of the (A)

Both (A) &(R) are true but the (R) is not the correct explanation of the (A)

(A) is true but (R) is false

Both (A) and (R) are false

Solution:

The energy density of an EM wave involves \(E^2\) and \(B^2\), which oscillate at \(2omega\). So, A is true. The average magnitudes of \(E\) and \(B\) over a half-cycle are not equal because \(E_0 = cB_0\). So, R is true. However, R does not explain A.

Rankers Physics

Energy Oscillation in EM Wave

Solution:

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