Section: C
Write the answer of the following questions in short:
23. State the difference between contact force and non contact force.
24. Write three physical properties of metal.
25. What is the difference between manure and fertiliser?
Answers
Answer:
23) Contact force : The force which acts between the bodies in their direct physical contact is known as contact force
example: Muscular force , frictional force
Non contact force : The force which acts between where there is no direct physical contact between them or the force between the two magnets of opposite sides . example : Gravitational force
24) Malleable, ductile, Luster, Good conductor of heat and electricity
25) Fertilizer: It is a human made or natural substances,that can be added to the soil to improve its fertility and increase the productivity. They are prepared in factories. It does not provide humus to the soil.
Manure : It is a natural material obtained by decaying plants and animal waste that can increase the fertility of the soil.It is prepared in fields. It provides more humus to the soil.