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 |
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. | \(1.2 \times 10^8~\text{m/s}\) |
A rod of glass \((\mu = 1.5)\) and of the square cross-section is bent into the shape as shown. A parallel beam of light falls on the plane flat surface \(A\) as shown in the figure. If \(d\) is the width of a side and \(R\) is the radius of a circular arc then for what maximum value of \(\frac{d}{R},\) light entering the glass slab through surface \(A\) will emerge from the glass through \(B\)?
1. | \(1.5\) | 2. | \(0.5\) |
3. | \(1.3\) | 4. | None of these |
For the given incident ray as shown in the figure, in the condition of the total internal reflection of this ray, the minimum refractive index of the prism will be:
1. | \(\dfrac{\sqrt{3} + 1}{2}\) | 2. | \(\dfrac{\sqrt{2} + 1}{2}\) |
3. | \(\sqrt{\dfrac{3}{2}}\) | 4. | \(\sqrt{\dfrac{7}{6}}\) |