Question 1: What is the law of reflection?

Answer: The angle of incidence equals the angle of reflection, measured relative to the normal to the surface.

Question 2: Describe how the normal line is used in measuring angles of incidence and reflection.

Answer: The normal line is an imaginary line perpendicular to the surface at the point of incidence, serving as the reference for measuring angles.

Question 3: In a reflection experiment, if the angle of incidence is 30°, what is the angle of reflection?

Answer: 30°

Question 4: Identify three types of surfaces that can cause regular reflection.

Answer: Smooth surfaces such as mirrors, calm water surfaces, and polished metals.

Question 5: Explain why a mirror forms a clear image of an object.

Answer: A mirror forms a clear image because it provides a smooth, reflective surface that causes light rays to reflect in a predictable manner, following the law of reflection. This regular reflection maintains the direction and coherence of the reflected rays, enabling the formation of a sharp, virtual image that appears to be behind the mirror.

Question 6: A ray of light strikes a mirror at an angle of 45° to the normal. What is the angle of reflection?

Answer: 45°

Question 7: Which of the following surfaces would produce a diffuse reflection? A) A polished metal surface B) A rough concrete wall C) A still pond surface D) A mirror

Answer: B) A rough concrete wall

Question 8: Fill in the blank: When light reflects off a surface, the angle of incidence is measured relative to the ________.

Answer: normal

Question 9: Describe one safety precaution that should be taken during a practical reflection experiment.

Answer: Wearing safety goggles to protect eyes from bright reflections or accidental splashes of reflective liquids.

Question 1: Design a simple experiment to demonstrate the law of reflection using a plane mirror and a light source. Identify the variables you would control and measure.

Answer: Arrange a plane mirror on a stable surface, shine a narrow beam of light at a known angle onto the mirror, and measure the angles of incidence and reflection using a protractor. Control variables include the surface of the mirror, the position of the light source, and environmental conditions like light intensity. Measure the angles relative to the normal to verify that the angle of reflection equals the angle of incidence.

Question 2: Explain how the reflection of light is utilised in the design of periscopes used in submarines.

Answer: Periscopes use mirrors arranged at specific angles to reflect light from above the water surface down to the viewer's eye, allowing them to see over obstacles or the water surface without exposing themselves.

Question 3: Identify one environmental or safety concern associated with using mirrors in large-scale industrial settings.

Answer: Potential glare and reflection of intense sunlight can cause eye hazards or fire risks if not properly managed.