CBSE 2026 · Region 2 · Set 3 · Q7 · 1 mark
The electric field and the magnetic field components of an electromagnetic wave travelling in vacuum are represented as $\displaystyle \mathrm{E}=\mathrm{m} \sin (\alpha \mathrm{z}-\beta \mathrm{t})$ $\displaystyle \mathrm{B}=\mathrm{n} \sin (\alpha \mathrm{z}-\beta \mathrm{t})$ where m, n, $\displaystyle \alpha$ and $\displaystyle \beta$ are constants characterising the wave. Then
Official answer
From CBSE’s own marking scheme for this paper.
(D)
$\displaystyle \frac{\mathrm{m}}{\mathrm{n}}=\frac{\beta}{\alpha}=\mathrm{c}$
Electromagnetic WavesUnderstandmcqmedium
More from Electromagnetic Waves
- The ratio of amplitude of electric field to the amplitude of the magnetic field associated with an…2026 · asked 3×
- The magnetic field in a plane electromagnetic wave travelling in glass (n=1 · 5) is given by B y=(2 × 10^-7…2026 · asked 3×
- A plane electromagnetic wave travels through a medium and the magnetic field associated with it is given by…2026 · asked 3×
- How are infrared waves produced? Why are these waves referred to as heat waves? Give any two uses of infrared…2023 · asked 3×
- What is meant by the term 'displacement current'? Briefly explain how this current is different from a…2023 · asked 3×
- Identify electromagnetic waves which: (i) are used in radar system. (ii) affect a photographic plate. (iii)…2022 · asked 3×
- Which of the following electromagnetic waves has photons of largest momentum?2025 · asked 3×
- (i) Depict a plane electromagnetic wave propagating along the x-axis. Write the expressions for its…2022 · asked 3×
CBSE Class 12 Physics past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.