Background information
- Normal: The perpendicular line drawn to the reflective surface.
- Incident ray: The ray of light hitting the reflective surface.
- Reflective ray: The ray of light coming off the reflective surface.
- Angle of incidents: The angle between the normal and the incident ray.
- Angle of reflection: The angle between the normal and the reflective ray.
Aim
To determine the relationship between the angle of incidents and the angle of reflection.
Equipment list
- Power pack
- Ray box
- Narrow light slit adapter
- Ruler
- Protractor
- Flat mirror
Method
- Connect the ray box to the power pack’s DC terminals and turn the power pack to 6 volts.
- Place the narrow slit adapter into the slit furthest from the light bulb in the ray box.
- Take the flat mirror from the ray box and trace along its surface on the edge of a piece of paper, with a pencil.
- At the midpoint of the line that was just drawn, draw the normal.
- Place the flat mirror back on the piece of paper where you traced it.
- Take the ray box and shine a single beam of light at the point where the normal meets the mirror.
- Using a pencil place 3 dots in the middle of the incident ray, and 3 dots in the middle of the reflected ray.
- Join the first 3 dots to the point where the normal meets the surface, then repeat this with the other 3 dots.
- Measure the angle of incidents and the angle of reflection.
- Repeat steps 3-9 using a different light ray angle.