The soles of our shoes get worn out after a period of time. It is due to ___________

On smooth surfaces, there are _________ number of irregularities. While on rough surfaces, there are ________ number of irregularities.

Spring balance is a device used for measuring the ________ acting on the object.

Cars and speedboats are _______ to reduce drag.

Friction can never be entirely __________

We pour a drop of oil on the hinge of door to __________ friction.

The substances are used in machines to protect their surfaces from wear and tear caused by ___________ are called lubricants.

All objects moving in fluids have ________ shape to reduce friction.

Smooth surfaces produce ________ friction than rough surfaces.

Ball bearings reduce friction because they rolls rather than ___________

________ is produced by friction.

Static friction is ________ than the sliding friction.

Sliding friction is __________ than the static friction.

Sprinkling of powder on the carrom board ________ friction.

Friction produces _________ 

Friction depends on the _________ of surfaces.

Friction opposes the  __________ between the surfaces in contact with each other.

In a large commercial complex there are four ways to reach the main road. One of the paths has loose soil, the second is laid with polished marble, the third is laid with bricks and the fourth has gravel surface. It is raining heavily and Paheli wishes to reach the main road. The path on which she is least likely to slip is :

The fishes swim easily in the water because they have

Treads are made in the tyres to

A boy rolls a rubber ball on a wooden surface. The ball travels a short distance before coming to rest. To make the same, ball travel longer distance before coming to rest, he may

Rolling friction is smaller than

Which of the following statements is incorrect?

Fine powder is poured on the carromboard to

If we apply oil on door hinges, the friction will

We can increase the friction by

A toy car released with the same initial speed will travel farthest on

To sharpen the blade of a knife by rubbing it against a surface, which of the following will be most suitable?

In figure, a boy is shown filushing the box trom right to left.

The force of friction will act on the box

It is difficult to walk on a wall polished floor because friction between our feet and floor is

Whenever the surfaces in contact tend to move or move with respect to each other, the force of friction comes into play

Friction is due to

The force of friction always

Alida runs her toy car on dry marble floor, wet marble floor, newspaper and towel spread on the floor. The force of friction acting on the car on different surfaces in increasing order will be

Four children were asked to arrange forces due to rolling, static and sliding frictions in a decreasing order. Their arrangements are given below. Choose the correct arrangement.

Striking a match stick produces fire by friction.

Use of lubricants increases the friction.

Use of ball bearing between the hubs is the example of rolling friction.

The friction force also depends on the shape of the object and the nature of fluid.

The friction force on an object in a fluid depends only on its speed.

Friction depends on nature of surfaces in contact.

Heat is produced due to friction.

Friction does not cause any wastage of energy.

Friction can be entirely eliminated.

Friction increases with mass of objects in contact.

Friction is harmful always.

It is easy to roll the body over one another thanto slide it.

Fluid friction depends on the shape of an object placed in the fluid and nature of fluid.

Friction increases with increase in smoothness of surface.

Soapy floor is slippery due to less friction.

Friction is a necessary evil

Gases are only called fluids.

Birds and fishes have streamlined shape.

Ball bearing is a device which converts static friction into sliding friction.

Friction enables vehicles to move on the ground.

Static friction is greater than rolling friction.

Friction always works in the same direction of motion of body

Ball Bearing

Fluid friction

Lubricants

Shape of aeroplane

Spring balance

Friction

Wheels

Ball bearing

Soapy floor

Lubricants

Friction produces

Can friction never be entirely eliminated?

Can we reduce friction to zero?

Why are soles of the shoes and the tyres of the vehicles treaded ?

What makes it difficult to walk on wet floor?

Name the friction that is overcome by most machines by the use of ball bearings. Name the type of friction with which it is replaced.

Name the friction when wheels are used to carry heavy weights.

Give an example which shows that friction can produce heat.

On what factor does force of friction depend?

Name the force that always opposes the applied force.