Transcript Aims

2_1 Forces between objects
06 April 2016
LO’s
• Recall terms action & reaction
• Recall unit of force
Match the quantities with their units.
Velocity
distance
Speed
Acceleration
time
© V Majer
m
m/s
m/s2
s
m/s
2_1 Forces between objects
06 April 2016
LO’s
• Recall terms action & reaction
• Recall unit of force
Match the quantities with their units.
Velocity
distance
Speed
Acceleration
time
m/s
m
m/s
m/s2
s
Isaac Newton explained how forces work.
His name is remembered as the unit of force.
What is a force?
• A push or a pull
• May be unbalanced or balanced
What does a force do?
• Gives energy
to an object
• Can set an
object in
motion, make it
stop, or change
its motion
Unbalanced forces change
motion
Weight and mass
•
•
Forces are measured in
Newtons
A Newton-meter measures forces.
Use the equipment to find the connection.
Mass (g)
Weight (N)
Weight (N)
mass
0
50
100
150
200
What would a graph of mass vs weight look like?
Be careful of any
zero error –
meter does not
read zero with no
force.
What does
this column
tell you
about the
connection?
Newton’s Third Law
“For every action, there is an equal
and opposite reaction.”
Or – Why would I get wet if I tried this?
For every action, there is an
equal and opposite reaction
The gases
being expelled
is the action.
The rocket
propelling
forward is the
reaction.
•
What have I learnt?
Use these words; Downwards equal opposite upwards
• The force on a ladder resting against a
opposite
equal
wall is ……………..
and …………………to
the
force of the wall on the ladder
• A book is at rest on a table. The force
downwards
of the book on the table …………..
The force of the table on the book is
upwards
……………….
Copy and complete
m3
Forces are represented by
vectors (size and direction)
Copy
Aims
All
Know that whenever 2 objects push or pull on each
other they exert equal and opposite forces on
each other
Recall unit of force
Most
Be able to draw diagrams to demonstrate forces
acting
Be able to explain resultant force
Some
Be able to explain how friction makes a car move.
The End