1. | equal to \(\sin ^{-1}\left(\frac{2}{3}\right)\) |
2. | equal to or less than \(\sin ^{-1}\left(\frac{3}{5}\right)\) |
3. | equal to or greater than \(\sin ^{-1}\left(\frac{3}{4}\right)\) |
4. | less than \(\sin ^{-1}\left(\frac{2}{3}\right)\) |
1. | \(30^\circ\) | 2. | \(37^\circ\) |
3. | \(53^\circ\) | 4. | \(45^\circ\) |
A rainbow is formed due to:
1. | Scattering & refraction |
2. | Total internal reflection & dispersion |
3. | Reflection only |
4. | Diffraction and dispersion |
Light enters at an angle of incidence in a transparent rod of refractive index \(n\). For what value of the refractive index of the material of the rod, will the light, once entered into it, not leave it through its lateral face whatsoever be the value of the angle of incidence?
1. \(n>\sqrt{2}\)
2. \(1.0\)
3. \(1.3\)
4. \(1.4\)
1. | \(90^{\circ}\) |
2. | \(180^{\circ}\) |
3. | \(0^{\circ}\) |
4. | equal to the angle of incidence |
Assertion (A): | Critical angle of light passing from angle to air is minimum for violet colour. |
Reason (R): | The wavelength of violet light is greater than the light of other colours. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Statement I: | In total internal reflection, the angle of incidence must be greater than a certain minimum angle which depends on the media involved. |
Statement II: | Total internal reflection cannot occur when light is travelling from an optically rarer to a denser medium. |
1. | Statement I is incorrect and Statement II is correct. |
2. | Both Statement I and Statement II are correct. |
3. | Both Statement I and Statement II are incorrect. |
4. | Statement I is correct and Statement II is incorrect. |
If \(C_1,~C_2 ~\mathrm{and}~C_3\) are the critical angle of glass-air interface for red, violet and yellow color, then:
1. | \(C_3>C_2>C_1\) | 2. | \(C_1>C_2>C_3\) |
3. | \(C_1=C_2=C_3\) | 4. | \(C_1>C_3>C_2\) |
A fish is a little away below the surface of a lake. If the critical angle is \(49^{\circ}\), then the fish could see things above the water surface within an angular range of \(\theta^{\circ}\) where:
1. | \(\theta = 49^{\circ}\) | 2. | \(\theta = 90^{\circ}\) |
3. | \(\theta = 98^{\circ}\) | 4. | \(\theta = 24\frac{1}{2}^{\circ}\) |
1. | \(1.8 \times 10^8 ~\text{m/s}\) | 2. | \(2.4 \times 10^8~\text{m/s}\) |
3. | \(3.0 \times 10^8~\text{m/s}\) | 4. | \(1.2 \times 10^8~\text{m/s}\) |