Refraction through Multiple Spherical Surfaces

Q.

A parallel beam of light travelling in water (refrative index = $\frac{4}{3}$) is refracted by a spherical air bubble of radius 2 mm situated in water. Assuming the light rays to be paraxial, locate the position of the final image.

1. -5 mm

2. -6 mm

3. 5 mm

4. 6 mm

Q. A crystal ball is $20cm$ in diameter with $\text{R. I}.=1.5$. If a gypsy lady is $1.2m$ from the ball, where is the image of the gypsy as seen from the other side?

1. $6.9cm$ from the crystal ball
2. $7.9cm$ from the crystal ball
3. $8.9cm$ from the crystal ball
4. None of these

Q. The diameter of aperature of a plano convex lens is 6 cm and its maximum thickenss is 3 mm. If the velocity of light in the material of lens is $2\times {10}^{8}m{s}^{-1}$, calculate the focal length of the lens

1. 10 cm
2. 15 cm
3. 20 cm
4. 30 cm

Q. A ray of light falls on the surface of a spherical glass paper weight making an angle $\alpha$ with the normal and is refracted in the medium at an angle $\beta$. The angle of deviation of the emergent ray from the direction of the incident ray is

1. $(\alpha -\beta )$
2. $2(\alpha -\beta )$
3. $\frac{(\alpha -\beta )}{2}$
4. $(\alpha +\beta )$