Question

11. Friction is caused by the irregularities on the two surfaces in contact. Even those surfaces which
appear very smooth have a large number of minute irregularities on them. Irregularities on the two
surfaces lock into one another. When we attempt to move any surface, we have to apply a force to
overcome interlocking On rough surfaces, there are a larger number of irregularities. So the force
12. For fires involving electrical equipment and inflammable materials like petrol, carbon dioxide is the
best extinguisher. Carbon dioxide, being heavier than oxygen, covers the fire like a blanket. Since
of friction is greater if a rough surface is involved.
the contact between the fuel and oxygen is cut off, the fire is controlled. The added advantage of
What wa
a) How the friction is caused?
b) Name the different forms of surfaces. How they are made up of?
c) How we can overcome from the interlocking of particles?
d) which form of surface shows the more force of friction?
carbon dioxide is that in most cases it does not harm the electrical equipment.
a) What is inflammable substance?
b) Which is the best fire extinguisher?
c) How does carbon dioxide extinguish the fire?
d) Name the advantage of the carbon dioxide?​

Answer 1

Explanation:

11. Friction is caused by the irregularities on the two surfaces in contact. Even those surfaces which

appear very smooth have a large number of minute irregularities on them. Irregularities on the two

surfaces lock into one another. When we attempt to move any surface, we have to apply a force to

overcome interlocking On rough surfaces, there are a larger number of irregularities. So the force

12. For fires involving electrical equipment and inflammable materials like petrol, carbon dioxide is the

best extinguisher. Carbon dioxide, being heavier than oxygen, covers the fire like a blanket. Since

of friction is greater if a rough surface is involved.

the contact between the fuel and oxygen is cut off, the fire is controlled. The added advantage of

What wa

a) How the friction is caused?

b) Name the different forms of surfaces. How they are made up of?

c) How we can overcome from the interlocking of particles?

d) which form of surface shows the more force of friction?

carbon dioxide is that in most cases it does not harm the electrical equipment.

a) What is inflammable substance?

b) Which is the best fire extinguisher?

c) How does carbon dioxide extinguish the fire?

d) Name the advantage of the carbon dioxide?