SSLC (English Medium) Class 7 - Tamil Nadu Board of Secondary Education Question Bank Solutions

True or False. If false, give the correct answer.

A bean plant collecting sunlight and turning it into bean seeds is an example of physical and non-periodic change.

True or False. If false, give the correct answer.

If the chemical properties of a substance remain unchanged and the appearance or shape of a substance changes it is called a periodic change.

Forest fire: ______ change::Change in period in a school: periodic change

State two examples of periodic changes.

Growing of nails is a periodic change. Why?

Is solar eclipse a periodic change? Give your reason.

What do you mean by visible light?

An electric component used as a safety device is electric circuit is ______.

An MCB can be used instead of a fuse in an electrical circuit.

An electric fuse has a body made of ceramic and two points for connecting the fuse wire.

What are the uses of electromagnets?

What is an electric fuse made up of?

What are the factors affecting heating effect of electric current?

Explain the working of an electric fuse.

______ are diploblastic.

Name the following:

A phylum with diploblastic animals.

White light is composed of ______.

If we mix lights of the colours of the rainbow we will get ______. 

When all colours of visible light strikes the retina of our eye at the same time, our brain perceives ______.

______ colour is scattered the least by air molecules.