100+ GK Current Affairs Questions and Answers Pdf - 2

Question: 6

What is a spectrum?

The coloured patch of light produced by passing a beam of white light rays through a prism is called spectrum.

Question: 7

Name the colours in the spectrum?

The spectrum consists of seven colours, namely Violet, Indigo, Blue, Green, Yellow, Orange and Red. The band of colours is called VIBGYOR.

Question: 8

What is refraction?

Refraction is the bending of light rays as it passes from one medium to another medium.

Question: 9

Why a concave lens is called a diverging lens?

A parallel beam of light rays after refraction through a concave lens diverges. Therefore it is called a diverging lens.

Question: 10

What is totally reflecting prism?

A prism having an angle of 90° between its two refracting surfaces and the other two angles each equal to 45° is called a totally reflecting prism.