What is meant by the reflection of light? Reflection of light refers to the process of sending back, or bouncing light rays when they encounter a reflecting surface - Leaving Cert Physics - Question 7 - 2005

1. The incident ray, reflected ray, and normal at the point of incidence all lie in the same plane.

2. The angle of incidence (i) is equal to the angle of reflection (r).

Apparatus: Ray box, drawing pins, mirror.

Procedure: Place the ray box to emit light rays onto the mirror. Use drawing pins to measure and mark the angles of incidence and reflection. Observe that the incident ray, reflected ray, and normal align according to the measurements taken. A labelled diagram will indicate the positions of these rays.

Refraction is the bending of light as it passes from one medium to another, which occurs due to a change in speed at the boundary of the mediums.

This angle is referred to as the critical angle.

Using the formula:

$n = \frac{\sin i}{\sin r}$

Substituting the given value:

$n = \frac{\sin 41.8^\circ}{0.67}$

Calculating gives approximately 1.22.

The diagram should illustrate that the ray is reflected at the boundary when the angle of incidence increases to 45°.

An application of this effect is found in optic devices such as periscopes, which use reflection to allow viewing around obstructing objects.