Sample 1Medium
Assertion (A): Electromagnetic waves carry momentum and exert pressure on a surface they fall on. Reason (R): In an electromagnetic wave the electric and magnetic fields are perpendicular to the direction of propagation.
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The answer is B.
Both statements are true: EM waves transport momentum (radiation pressure), and they are transverse. Their transverse nature does not explain why they carry momentum.
- A.
Transverse nature does not explain why EM waves carry momentum; the momentum is tied to the energy they carry (p = U/c).
- C.
Reason is true: E and B are perpendicular to the direction of propagation.
- D.
Assertion is true: EM waves carry momentum and exert radiation pressure.
NCERT: Class 12 Physics, Chapter 8, Electromagnetic waves