FRICTION
What is force of friction?
The force acting along the two surfaces in contact that opposes the motion of
one object over the other is called the force of friction.
Example: A ball rolling along the ground gradually
slows down and finally comes to rest.
While cycling when you stop pedalling a bicycle, it gradually slows down and
finally comes to rest.
List the effects of Friction.
Friction opposes the relative motion between two surfaces in contact.
It acts on both the surfaces.
The force of friction always opposes the applied force.
The force of friction produces heat
“Every surface is but the degree of roughness varies.” How does the
roughness of surface appear when seen through the microscope?
The roughness of the surface can be seen through a microscope in the form of
tiny hills and valleys.
Explain the cause of force of friction
The huge number of minute irregularities that are
present between the two surfaces in contact lock
into one another get entangled with one another.
The interlocking of the two surfaces opposes the
motion of one object over another and gives rise to
frictional force
, How does force of friction vary on the number of irregularities?
On rough surfaces, there are a larger number of irregularities, so the force of
friction is greater. Whereas on a smooth surface, the force of friction is less.
If there are two very smooth surfaces, will there be an interlocking
observed between them?
When two surfaces are in contact are smooth, then the friction between them is
small because the interlocking of smooth surface is less.
What is a spring balance?
Spring balance is a device that is used for measuring
the force acting on an object. It consists of a coiled
spring that gets stretched once a force is applied to
it. Stretching of the spring is measured by a moving
pointer on a graduated scale. The reading on the scale
provides the magnitude of the force.
List the factors affecting force of friction
The nature of surfaces in contact with each other: Rough surfaces
have more friction, smooth surfaces have less friction.
The weight of the object: More weight has more friction, less weight has
less friction
Activity to show that friction depends on the smoothness of surfaces
How does change in weight effects friction?
While moving a heavy box and a lighter box, a heavy box has a strong
interlocking with the surface since the two surfaces are tightly pressed so we
What is force of friction?
The force acting along the two surfaces in contact that opposes the motion of
one object over the other is called the force of friction.
Example: A ball rolling along the ground gradually
slows down and finally comes to rest.
While cycling when you stop pedalling a bicycle, it gradually slows down and
finally comes to rest.
List the effects of Friction.
Friction opposes the relative motion between two surfaces in contact.
It acts on both the surfaces.
The force of friction always opposes the applied force.
The force of friction produces heat
“Every surface is but the degree of roughness varies.” How does the
roughness of surface appear when seen through the microscope?
The roughness of the surface can be seen through a microscope in the form of
tiny hills and valleys.
Explain the cause of force of friction
The huge number of minute irregularities that are
present between the two surfaces in contact lock
into one another get entangled with one another.
The interlocking of the two surfaces opposes the
motion of one object over another and gives rise to
frictional force
, How does force of friction vary on the number of irregularities?
On rough surfaces, there are a larger number of irregularities, so the force of
friction is greater. Whereas on a smooth surface, the force of friction is less.
If there are two very smooth surfaces, will there be an interlocking
observed between them?
When two surfaces are in contact are smooth, then the friction between them is
small because the interlocking of smooth surface is less.
What is a spring balance?
Spring balance is a device that is used for measuring
the force acting on an object. It consists of a coiled
spring that gets stretched once a force is applied to
it. Stretching of the spring is measured by a moving
pointer on a graduated scale. The reading on the scale
provides the magnitude of the force.
List the factors affecting force of friction
The nature of surfaces in contact with each other: Rough surfaces
have more friction, smooth surfaces have less friction.
The weight of the object: More weight has more friction, less weight has
less friction
Activity to show that friction depends on the smoothness of surfaces
How does change in weight effects friction?
While moving a heavy box and a lighter box, a heavy box has a strong
interlocking with the surface since the two surfaces are tightly pressed so we
