1. Friction As a Necessary Evil

2. Friction
 An opposing force called into plain, when two surfaces in
contact with each other tend to slide relative to one another
is called friction.

3. Example
Sander on a Piece of Wood = High Degree of Friction

4. Types of Friction
 Static Friction
 Limiting Friction
 Sliding Friction

5.  Friction as a necessity
Friction
As A
Necessity
it produces heat and
slows down moving
bodies.
 If there were no
friction, the bodies
will either slip or
not move.

6. Benefits Of Friction
Striking a matchstick
We are able to drive automobiles
Spiked shoes of cricket
players
Writing on paper

7. Disadvantages Of Friction
Noise pollution is caused
Forest fires are caused

8. Friction AS An Evil
 Friction as an evil Friction brings about wear and
tear in moving bodies .
 It produces heat and slows down moving bodies.
 A lot of energy is wasted in overcoming friction.

9. Is Friction good or bad?

10. Friction can be a good
 When
we walk we push
backwards
against the ground,
the opposing force
pushes us forwards.
 Without
friction , our feet
would slip and walki
ng would
be impossible.

11. Friction can be bad
 Soil erosion caused by wind (friction of a fluid).
 Holes in your shoes, jeans. (friction of a solid) high
friction.
 Lack of friction is dangerous too, you may fall if the
floor is very slippy.