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:

1.	\(-3f\)	2.	\(1.5f\)
3.	\(-1.5f\)	4.	\(3f\)

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:

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

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