1. | \(10\) m/s2 |
2. | \(20\) m/s2 |
3. | \(5\) m/s2 |
4. | can't be determined |
A light ray is incident at an angle of \(30^{\circ}\) on a transparent surface separating two media. If the angle of refraction is \(60^{\circ}\), then the critical angle is:
1. \(\sin^{- 1} \left(\frac{1}{\sqrt{3}}\right)\)
2. \(\sin^{- 1} \left(\sqrt{3}\right)\)
3. \(\sin^{- 1} \left(\frac{2}{3}\right)\)
4. \(45^{\circ}\)
In the figure shown the angle made by the light ray with the normal in the medium of refractive index \(\sqrt{2}\) is:
1. \(30^{\circ}\)
2. \(60^{\circ}\)
3. \(90^{\circ}\)
4. None of these
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. | \(\theta = 24\frac{1}{2}^{\circ}\) |
An object is placed at a point distance \(x\) from the focus of a convex lens and its image is formed at \(I\) as shown in the figure. The distances \(x\) and \(x'\) satisfy the relation:
1. \(\frac{x+x'}{2} = f\)
2. \(f = xx'\)
3. \(x+x' \le 2f\)
4. \(x+x' \ge 2f\)
The diameter of the eye-ball of a normal eye is about 2.5 cm. The power of the eye lens varies from:
1. 2 D to 10 D
2. 40 D to 32 D
3. 9 D to 8 D
4. 44 D to 40 D
1. | \(90^{\circ}\) |
2. | \(180^{\circ}\) |
3. | \(0^{\circ}\) |
4. | equal to the angle of incidence |
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. | \(1.2 \times 10^8~\text{m/s}\) |
1. | \(207\) cm | 2. | \(210\) cm |
3. | \(204\) cm | 4. | \(220\) cm |
On an optical bench a point object is placed at the mark of \(10\) cm, a convex lens of focal length \(15\) cm at the mark of \(40\) cm and a concave lens of focal length \(15\) cm placed at the mark of \(60\) cm. The final image is formed at the mark of: (point object and two lenses are coaxial)
1. \(30\) cm
2. \(80\) cm
3. \(90\) cm
4. infinity