Practice Sheets on Light Reflection & Refraction

Light reflection and refraction Worksheet-16

1. A coin in a glass beaker appears to rise as the beaker is slowly filled with water. Why ?

2. A tank of water is 4 m deep. How deep does it appear when seen normally?

3. What is meant by optical centre of a lens ?

4. Define first principal focal length of a convex lens.

5. What is the difference between a real image and a virtual image?

6. What is linear magnification produced by a lens? How is it related to object distance and image distance?

Light reflection and refraction Worksheet-17

1. The refractive index of glass is 3/2 and refractive index of water is 4/3. What would be the refractive index of water with respect to glass?

2. What are the conditions for no refraction of light ?

3. A ray of light passing through centre of curvature of a spherical mirror retraces its path on reflection from the mirror.

4. A concave mirror is used as a head mirror by ENT specialists. The same mirror can also be used as a shaving mirror. Why?

5. State mirror formula. How does f change when object distance u from the mirror is changed ?

Light reflection and refraction Worksheet-18

1. A convex lens of focal length 20 cm is placed in contact with a concave lens of focal length 10 cm. What is the focal length and power of the combination?

2. If the magnification of a body of size 1 m is 2, what is the size of the image ?

3. What is the power of a concave lens of focal length 25 cm ?

4. What will be the focal length of a lens whose power is given as + 2.0 D ?

5. Where will the image be formed by a concave mirror when an object is placed between the pole and the focus point of the mirror ?