Light can be diffracted, refracted and reflected. However, during all these processes light travels in a straight line. We understood this through the smoke tank practical in which the ray of laser could be seen clearly.
During the experiment, in order to investigate reflection, a mirror was placed in the box. The laser light hit the mirror and reflected back to the way it came from therefore there were two rays of lights, one, which was being shone onto the mirror and the other, being reflected off the mirror.
A dense sheet of glass was placed before the light. When the light was shone through the glass surface, the ray changed its angle, bending slightly (refracting) once it penetrated through the glass surface.
Diffraction occurred when a slit was placed before the light. The light was shone into the slit and as it passed out of the small hole, the ray became wider.
Why do we see objects?
We see things due to light. Some objects are simply sight sources such as the sun. However, views of other objects, such as the moon, are reflected into your eye. The light hits the object and some of the light is reflected into your eye.
There are some objects which you can see through though. These objects are considered 'transparent'
On the other hand, objects which still reflect light but do not allow us to see through them are known as 'opaque'.
Angle of incidence and reflection
A mirror was placed at the bottom of a protractor and a normal was drawn across the front of the mirror.
Rays of light were shone at different angles to the normal, which was drawn across the front of the mirror. The angle of the light being shone (angle of incidence) and reflected (angle of reflection) were measured and recorded.
After we recorded our results, we found out that the angle of incidence=angle of reflection.
