Download resultant force

Force and motion
Revise the following:
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Distance time graphs
Velocity-time graphs
Resultant force
Terminal velocity
Stopping distances
Distance time graph
Distance time graph
Distance time graph
Velocity-time graph
Velocity-time graph
Velocity-time graph
Velocity-time graph
Distance-time graph
Velocity-time graph
Resultant forces
There are usually several different forces acting on an
object. The overall motion of the object will depend on the
size and direction of all the forces.
The motion of the object will depend on the resultant
force. This is calculated by adding all the forces
together, taking their direction into account.
50 N
30 N
Resultant force on the crate = 50 N – 30 N
= 20 N to the left
Resultant force
Object at the
start
Resultant
force
Effect on the object
Stationary
Zero
Remain stationary
Stationary
Not zero
Accelerate in the direction of
the resultant force
Moving
Zero
Continue to move at same speed
in same direction
Moving
Not zero
Accelerate in the direction of
the resultant force
Resultant force
newton (N)
=
mass
x
acceleration
kilogram (kg) metre/second2 (m/s2)
Terminal velocity
• The faster a body moves through
fluid, the greater the frictional force
which acts on it.
• A body falling through a fluid will
initially accelerate due to the force of
gravity.
• Eventually the resultant force on the
body will be zero and it will fall at its
Terminal velocity
Stopping distance