Colour of an object

Question 1

What is specular reflection?

Answer 1

Specular reflection occurs when waves are reflected from a smooth surface. When parallel rays of light are incident on a smooth, plane surface such as a mirror, the reflected light rays will also be parallel. The sizes of any irregularities on the surface are much smaller than the wavelength of the wave.

Question 2

What is diffuse reflection?

Answer 2

Diffuse reflection occurs when the surface is not smooth and has rough irregularities. The size of the irregularities is comparable with the wavelength of the wave. The incident wave is then reflected at many different angles, and the reflected rays will not be parallel, such as when light is reflected off a painted wall.

Question 3

What is the colour spectrum?

Answer 3

Visible light makes up a very small part of the electromagnetic spectrum. The colours that we see can be split into different colours by a prism. These colours all have a different wavelength, ranging from the longest wavelength at the red end of the spectrum to the shortest wavelength at the violet end.