Reflection Laws and Spherical Mirrors - UNSOLVED PRACTICE SET
Chapter: Ray Optics and Optical Instruments | Topic: Reflection Laws and Spherical Mirrors
REFLECTION LAWS AND SPHERICAL MIRRORS - UNSOLVED PRACTICE SET
Topic: Reflection Laws and Spherical Mirrors
Multiple Choice Questions
Q1. The angle of incidence is equal to the angle of reflection. This law of reflection holds for:
- Plane mirrors only
- Spherical mirrors only
- All types of reflecting surfaces
- Polished surfaces only
Q2. The focal length of a spherical mirror is related to its radius of curvature by:
- f = R/2
- f = 2R
- f = R
- f = R²
Q3. A concave mirror forms a real, inverted image of an object placed beyond its centre of curvature. The image is formed:
- Between the pole and the focus
- Between the focus and the centre of curvature
- Beyond the centre of curvature
- At the centre of curvature
Q4. A convex mirror always forms an image that is:
- Real and inverted
- Virtual and erect
- Real and erect
- Virtual and inverted
Q5. The image formed by a plane mirror is:
- Real and of the same size as the object
- Virtual, erect, and laterally inverted
- Real and magnified
- Virtual and diminished
Q6. When an object is placed at the focus of a concave mirror, the image is formed:
- At the centre of curvature
- At infinity
- Between F and C
- At the pole
Short Answer Questions
Q7. State the two laws of reflection of light. Illustrate with a ray diagram.
Q8. Define the following terms for a spherical mirror: (a) Pole, (b) Centre of curvature, (c) Radius of curvature, (d) Principal focus.
Q9. Why does a concave mirror converge parallel rays of light, while a convex mirror diverges them? Explain with ray diagrams.
Q10. A driver prefers a convex mirror as a rear-view mirror in vehicles. Give two reasons.
Q11. Why is the image formed by a plane mirror laterally inverted? Explain with a diagram.
Q12. What happens to the image formed by a concave mirror when the object is moved from infinity towards the pole? Describe the changes in position, nature, and size of the image.
Long Answer Questions
Q13. Derive the mirror formula for a spherical mirror using the ray diagram method. State the sign convention used.
Q14. With the help of ray diagrams, show the image formation by a concave mirror when the object is placed at:
(a) Infinity
(b) Beyond C
(c) At C
(d) Between C and F
(e) At F
(f) Between F and P
Q15. Explain why convex mirrors are used as rear-view mirrors in vehicles and as security mirrors in shops. Discuss the advantages and limitations of using convex mirrors for these purposes.
Numerical & Application-Based Problems
Q16. An object is placed 30 cm in front of a concave mirror of focal length 10 cm.
(a) Calculate the position of the image.
(b) Calculate the magnification.
(c) Describe the nature of the image.
(d) Draw a ray diagram to illustrate the image formation.
Q17. A convex mirror has a radius of curvature of 40 cm. An object of height 5 cm is placed 20 cm in front of the mirror.
(a) Calculate the focal length of the mirror.
(b) Determine the position of the image.
(c) Calculate the height of the image.
(d) Describe the nature of the image formed.
Q18. In your school's science fair, a student sets up an experiment with a concave mirror to focus sunlight onto a piece of paper.
(a) If the mirror has a focal length of 15 cm, at what distance from the mirror should the paper be placed to get the brightest spot?
(b) The student notices that the spot becomes very hot and can burn the paper. Explain why this happens.
(c) The student then uses this same mirror to form an image of a candle flame placed 25 cm from the mirror. Calculate the image distance and magnification.
(d) A classmate suggests using a convex mirror instead to focus sunlight. Predict what would happen and explain why concave mirrors are preferred for solar concentrators.