An incident ray makes an angle of 90° with the mirror surface. The angle of reflection for this ray
Channel: Entrance Test
Date: 2021-10-20

An incident ray makes an angle of 90° with the mirror surface. The angle of reflection for this
ray is:
A. 90°
B. 0°
C. 30°
D. 45°

Correct option is
(answer 1)If the light ray makes an angle of 90∘ with the surface of the mirror, then
The angle of incidence =0∘
Therefore, angle of reflection =0∘
(answer 2) The answer to this is really simple….
Since angle of incidence is equal to the angle of reflection, we can also say that angle between the incident ray and reflected ray is twice the angle of reflection or incidence.
Thus, as per above case angle of incidence =(90/2) = 45 degree.

Reflection and refraction
Light rays change direction when they reflect off a surface, move from one transparent medium into another, or travel through a medium whose composition is continuously changing. The law of reflection states that, on reflection from a smooth surface, the angle of the reflected ray is equal to the angle of the incident ray. (By convention, all angles in geometrical optics are measured with respect to the normal to the surface—that is, to a line perpendicular to the surface.) The reflected ray is always in the plane defined by the incident ray and the normal to the surface. The law of reflection can be used to understand the images produced by plane and curved mirrors. Unlike mirrors, most natural surfaces are rough on the scale of the wavelength of light, and, as a consequence, parallel incident light rays are reflected in many different directions, or diffusely. Diffuse reflection is responsible for the ability to see most illuminated surfaces from any position—rays reach the eyes after reflecting off every portion of the surface.

Chapter 1 Chemical Reactions and Equations, Chapter 2 Acids Bases and Salts, Chapter 3 Metals and Non-Metals, Chapter 4 Carbon and Its Compounds, Chapter 5 Periodic Classification of Elements, Chapter 6 Life Process, Chapter 7 Control and Coordination, Chapter 8 How do Organisms Reproduce?, Chapter 9 Heredity and Evolution, Chapter 10 Light Reflection and Refraction, Chapter 11 Human Eye and Colourful World, Chapter 12 Electricity, Chapter 13 Magnetic Effects of Electric Current, Chapter 15 Our Environmenttop 10 important questions