A plane-convex lens of unknown material and unknown focal length is given. With the help of a spherometer, we can measure the

1.	focal length of the lens.
2.	radius of curvature of the curved surface.
3.	aperture of the lens.
4.	refractive index of the material.

An object is placed on the principal axis of a concave mirror at a distance of \(1.5f\) (\(f\) is the focal length). The image will be at:

If the critical angle for total internal reflection from a medium to vacuum is \(45^{\circ}\), the velocity of light in the medium is: 

The power of a biconvex lens is \(10\) dioptre and the radius of curvature of each surface is \(10\) cm. The refractive index of the material of the lens is:
1. \( \frac{4}{3} \)
2. \( \frac{9}{8} \)
3. \( \frac{5}{3} \)
4. \( \frac{3}{2}\)

For the angle of minimum deviation of a prism to be equal to its refracting angle, the prism must be made of a material whose refractive index:

A rod of length \(10~\text{cm}\) lies along the principal axis of a concave mirror of focal length \(10~\text{cm}\) in such a way that its end closer to the pole is \(20~\text{cm}\) away from the mirror. The length of the image is:
1. \(15~\text{cm}\) 
2. \(2.5~\text{cm}\)
3. \(5~\text{cm}\)
4. \(10~\text{cm}\)

A thin prism of angle \(15^\circ\) made of glass of refractive index \(\mu_1=1.5\) is combined with another prism of the glass of refractive index \(\mu_1=1.75.\) The combination of the prism produced dispersion without deviation. The angle of the second prism should be:
1. \(5^\circ\)
2. \(7^\circ\)
3. \(10^\circ\)
4. \(12^\circ\)

A converging beam of rays is incident on a diverging lens. Having passed through the lens the rays intersect at a point \(15~\text{cm}\) from the lens on the opposite side. If the lens is removed the point where the rays meet will move \(5~\text{cm}\) closer to the lens. The focal length of the lens is:
1.  \(5~\text{cm}\)
2. \(-10~\text{cm}\)
3. \(20~\text{cm}\)
4. \(-30~\text{cm}\)

The speed of light in media \(M_1\) and \(M_2\) is \(1.5\times10^{8}\) m/s and \(2.0\times10^{8}\) m/s respectively. A ray of light enters from medium  \(M_1\) and \(M_2\) at an incidence angle \(i.\) If the ray suffers total internal reflection, the value of \(i\) is:

A ray of light is incident on a \(60^\circ\) prism at the minimum deviation position. The angle of refraction at the first face (i.e. incident face) of the prism is:
1. \(30^\circ\)
2. \(45^\circ\)
3. \(60^\circ\)
4. zero