Advertisements
Advertisements
प्रश्न
In a beam of sunlight entering a room, we can sometimes see dust particles moving in a haphazard way in the air. Why do these dust particles move?
Advertisements
उत्तर
When a beam of sunlight enters a room, suspended dust particles are seen moving haphazardly. This is because the dust particles are constantly hit by the fast moving particles of air and due to this remain suspended despite gravity acting on them. This is an example of Brownian motion.
APPEARS IN
संबंधित प्रश्न
What do you mean by the inter-molecular spaces? How do they vary in different states of matter?
Name the terms for the particles of matter which may or may not have independent existence.
State two characteristics of matter demonstrated by Brownian motion.
When a gas jar containing air is inverted over a gas jar containing bromine vapour, the red-brown bromine vapour diffuse into air. Explain how bromine vapour diffuse into air.
Name two solid, two liquid and two gaseous elements at the room temperature.
Name a metal which can be easily cut with a knife.
Name a metal which has no fixed shape.
In the following set of substances, one item does not belong to the set. Select this item and explain why it does not belong to the set :
Hydrogen, Oxygen, Steam, Chlorine
Out of a colloid, solution and a suspension :
which one has the largest particles ?
Which of the following do not exhibit Tyndall effect ?
Starch solution, Sugar solution, Ink, Salt solution, Copper sulphate solution, Ammonium chloride solution, Fog, Smoke, Car exhausts.
What is a colloid ? Give two examples of colloids (or colloidal solutions)
What type of magnet is fitted on a crane to separate scrap iron objects from a heap of waste materials in factories ?
Name the process by which all the dye can be recovered from black ink.
Describe a method to separate a mixture of common salt and sand.
The material which is added to water during purification process at the water works so as to disinfect it is :
Explain the meaning of the term matter with special reference to the term ‘substance’.
Diffentiate between absorption and adsorption.
In Aerosol the dispersed phase is liquid and the dispersion medium is gas.
The movement of particles in liquids is ______.
