Atoms and Molecules — Science STD 9 — Question

State one use of radioactive isotopes in medicine.

Define the term impulse.

Name the process associated with the following:
Fine beam of light entering through a small hole in a dark room, illuminates the particles in its paths.

Explain how, the smell of food being cooked in the kitchen reaches us even from a considerable distance.

What name is given to the sound waves of frequency too low for humans to hear?

Name the conducting elements of phloem.

A carpenter wants to separate iron nails from saw-dust. Which method of separation should he choose?

What is prokaryotic cell?

Give one example the following.
Solution of a solid in solid.