Friction and Forces Quiz

Friction opposes the __________ motion between two surfaces in contact.

Answer explanation

Friction opposes the relative motion between two surfaces in contact.

Friction depends on: i) __________ of surfaces in contact. ii) State of __________ of surfaces.

Answer explanation

Friction depends on: i) Nature of surfaces in contact. ii) State of smoothness of surfaces.

Friction can be increased by making a surface __________.

Answer explanation

Friction can be increased by making a surface rougher.

Friction is __________ of the area of contact.

Answer explanation

Friction is independent of the area of contact.

Friction is caused by __________ on the two surfaces in contact.

Answer explanation

Friction is caused by the irregularities on the two surfaces in contact.

The sole of the shoes and the tyres of the vehicle are __________ to increase friction.

Answer explanation

The sole of the shoes and the tyres of the vehicle are treaded to increase friction.

The substances which reduce friction are called __________.

Answer explanation

The substances which reduce friction are called lubricants.

In many machines, friction is reduced by using ________________.

Answer explanation

In many machines, friction is reduced by using ball bearings.

Fluid friction can be minimized by giving suitable __________ to bodies moving in fluids.

Answer explanation

Fluid friction can be minimized by giving suitable shape to bodies moving in fluids.

The opposing force that comes into play when one body tends to move over the surface of another, but actual motion has yet not started is called __________ friction.

Answer explanation

The opposing force that comes into play when one body tends to move over the surface of another, but actual motion has yet not started is called static friction.