The speed of light depends:
1. | on elasticity of the medium only. |
2. | on inertia of the medium only. |
3. | on elasticity as well as inertia. |
4. | neither on elasticity nor on inertia. |
The equation of a light wave is written as \(y = A \sin (kx-\omega t).\) Here, \(y\) represents:
1. displacement of ether particles
2. pressure in the medium
3. density of the medium
4. electric field
When light propagates in a vacuum, there is an electric field and a magnetic field. These fields:
(A) | Are constant in time. |
(B) | Have zero average value. |
(C) | Are perpendicular to the direction of propagation of light. |
(D) | Are mutually perpendicular to each other. |
Choose the correct option from the options given below:
1. | (A) and (B) only |
2. | (B) and (C) only |
3. | (A), (B) and (C) only |
4. | (B), (C) and (D) only |
Three observers A, B and C measure the speed of light coming from a source to be VA, VB and VC. The observer A moves towards the source and C moves away from the source at the same speed. The observer B stays stationary. The surrounding space is vacuum everywhere.
(a) \(v_{A}>v_{B}>v_{C}\)
(b) \(v_{A}<v_{B}<v_{C}\)
(c) \(v_{A}=v_{B}=v_{C}\)
(d) \(v_{B}=\frac{1}{2}\left(v_{A}+v_{C}\right)\)
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (c) and (d)
4. All of these
Dimensions of 1/(µ0ε0) is
1. L/T
2. T/L
3. L2/T2
4. T2/L2
An electromagnetic wave going through vacuum is described by;
\(E=E_0 \sin (k x-\omega t) ; B=B_0 \sin (k x-\omega t).\)
Then:
1. \( E_0 k=B_0 \omega \)
2. \( E_0 B_0=\omega k \)
3. \( E_0 \omega=B_0 k\)
4. none of these
An electric field \(\vec E\) and a magnetic field \(\vec B\) exist in a region. The fields are not perpendicular to each other.
1. | This is not possible. |
2. | No electromagnetic wave is passing through the region. |
3. | An electromagnetic wave may be passing through the region. |
4. | An electromagnetic wave is certainly passing through the region. |
Consider the following two statements regarding a linearly polarized, plane electromagnetic wave:
Statement I: | The electric field and the magnetic field have equal average values. |
Statement II: | The electric energy and the magnetic energy have equal average values. |
1. | Both Statement I and Statement II are True. |
2. | Statement I is False but Statement II is True. |
3. | Statement II is False but Statement I is True. |
4. | Both Statement I and Statement II are Fale. |
A free electron is placed in the path of a plane electromagnetic wave. The electron will start moving:
1. | along the electric field |
2. | along the magnetic field |
3. | along the direction of propagation of the wave |
4. | in a plane containing the magnetic field and the direction of propagation |
An electromagnetic wave going through vacuum is described by
E = E0 sin(kx – ωt)
Which of the following is/are independent of the wavelength?
(a) k
(b) ω
(c) k/ω
(d) kω
Choose the correct option
1. (a), (b)
2. (b), (c)
3. (c) only
4. (a), (d)