Year 7 Forces
All About FRICTION
1. What is Friction? [ 3 points ]
Name: ______________________________ Form: _______
2. Write down at least 20 Daily Uses of Friction
No
Friction
No
1
11
2
12
3
13
4
14
5
15
6
16
7
17
8
18
9
19
10
20
Friction
3. Give 3 situations where friction becomes an advantage or a nuisance.
4. Describe 5 ways in which friction can be decreased or reduced.
No
Friction
No
Friction
1
Tie up shoe lace
11
Pulley wheels
2
12
3
Eraser - erasing an answer using a
rubber
Drying wet towel
4
Sand paper
14
Grind stone to sharpen chisels and
knives
Rubber balloons with your hair to
create statics
Pen cap
5
Nail File
15
Cork in bottle
6
File
16
Brake pad in car or bike
7
Plier
17
Tyres
8
Nail to the wood
18
9
Open screw top
19
Rub your hands together and feel
the warmth
Washing your hand properly
10
Turning door knob
20
Velcro in bags or shoes
21
Holding chopsticks
31
Scrubbing a plate
22
Striking a match
32
Brushing your teeth
23
33
Friction between paper (2 books)
24
Walking - if there is no friction
between your shoes/feet and the
floor, you would be slippering in one
place forever.
Running
34
Microfiber sponge for cleaning
25
Holding a pen
35
Moving object eventually stops
26
Chewing food
36
27
Maintaining balance
37
28
Keeps your pants on
38
29
Car moving forward
39
30
Friction belt in car or cooler
40
Meteors hitting the earths
atmosphere - the friction is what
causes the heat that makes them
burn up
Roll a penny and watch it stop.
Friction of the air and the rolling
resistance is what slows it down
It keeps us on our feet, have you
ever tried standing on a completely
frictionless surface?
Spinning and Smashing in Table
Tennis or Tennis
An object sitting on an included
plane
13
Definition of friction
1. Friction is the resistance that one surface or object encounters when moving over
another or a force that slows motion and dampens energy.
2. Friction is the force that resists relative motion between two bodies in contact.
3. Friction is a force which causes the motion between two surfaces to be reduced.
4. Friction is a force that is created whenever two surfaces move or try to move across each
other.
5. Friction is a force that acts in an opposite direction to movement.
Facts about friction
1. Friction always opposes the motion or attempted motion of one surface across another
surface.
2. Friction is dependant on the texture of both surfaces.
3. Friction is also dependant on the amount of contact force pushing the two surfaces together
(normal force).
4. Friction keeps us from slipping and falling everywhere.
5.
Ways to increase friction
1. Make the surface rougher
2. Use rough surface materials – eg. Carpet, cork
3. Increase the surface area – opening the parachute
Ways to decrease friction
1.
2.
3.
4.
5.
Smoothen the surface eg. Using very fine sand paper
Aerodynamic or streamline structures
Using lubricant, eg. Wax, oil, water, WD40 etc
Fluid between joints in animals
Swallowing – with water/ liquid or more saliva
Disadvantages of Friction
1.
2.
3.
4.
5.
6.
7.
8.
9.
Wearing out tyres and brake pads
Wearing out shoes
Heat produced by Engine – rubbing parts
Forest fires can be caused due to friction when the branches of trees rub against each
other.
Drag and water resistance slow down the moving object
Air resistance (drag) slow you from riding a bike or running
Opposing the motion
Producing noise – door hinge with too much friction.
Vehicle tyres on a roadway, a process which generates heat and sound
Types of Friction
1. Static friction: friction between two objects that are not moving relative to each other
2. Rolling Friction - associated with the rolling of a wheel or something circular along a
surface.
3. Kinetic or Sliding friction is friction where an object slides, or rubs against, another
surface.
4. Fluid friction is the friction of something going through any type of liquid or air.