To avoid slipping while walking on ice, one should take smaller steps because
Frictional force of ice is large
Of larger normal reaction
Frictional force of ice is small
Of smaller normal reaction
Special kinds of grooves are made in automobile tyres. This is done in order to
Increases friction.
Reduce Friction.
Increases the speed of rotation of the tyres.
for more style
The soles of our shoes have grooves. This is to
Increase the friction between shoes and the ground.
Make the shoes look more attractive.
Reduce the friction between the shoes and the ground.
Save on rubber used to make the soles.
Friction is a type of:
contact force.
non contact force.
resistance force.
motion.
The frictional force exerted by fluids is called
Lift.
Drag.
Rolling friction.
Dynamic friction.
The magnitude of a frictional force depends on
I. The surface area of contact.
II. The weight of the object.
III. The condition of the surface in contact.
I and II only
II and III only
III and I only
All of these
How does the proper inflation of tyre save fuel?
Normal reaction decreases
Normal reaction increases
Sliding contact with the road decreases
Sliding contact with the road increases
The minimum force required to make one body just slide over another body is called
Static friction.
Sliding friction.
Limiting friction.
With increase in weight of a body the limiting friction
Increases.
Decreases.
Does not change.
First increases and then decreases.
A meteor burns up on entering earth’s atmosphere due to
Stmospheric pressure.
Heat of the earth.
Solar radiation.
Excessive friction.