Homer has decided to start this lesson off with a helpful hint and has given
you the S.I. unit for momentum.
Can you use that to work out the two other factors that are involved in the
equation to calculate momentum?
The units for
momentum are
kg m/s
YOU need to
RECALL
&
APPLY
Momentum = mass x velocity
Factor
Unit
Energy
Joules (J)
Mass
kg
Speed
m/s
Gravitational field strength
N/kg
Height
metres (m)
Velocity
m/s
Distance
metres (m)
Displacement
metres (m)
Acceleration
m/s2
Work done
Joules (J)
Power
Watts (W)
Time taken
seconds (s)
Momentum
kg m/s
Force
Newtons (N)
One wintery day at the South Pole….
Peter Penguin (14kg) was sliding down
the slope
Momentum = mass x velocity
= 14 x 4
= 56 kg m/s
Now, if Peter
had a velocity
of 4 m/s
Then what is
his
momentum?
Welcome to the
MOMENTUM OLYMPICS
Look at the organisms and their details below. Work out the
order of these organisms in terms of their total momentum, from
the lowest to the highest
Two
meerkats,
each
12000g, who
move at 8m/s
Usain,
95kg,
moving at
10m/s
A 60kg
sheep
who is
stationary
Momentum = mass x velocity
Using an equation triangle and the cover-up rule (or
by rearranging the equation using your own
method), work out and write down the remaining
two equations which make mass and then velocity
the subject
mass
=
velocity
velocity==
momentum
÷
velocity
momentum
momentum
÷÷
mass
mass
Try questions 3
and 4
Use your three equations to try the
questions on calculating momentum
(q 1, 2 and 3)
Required response
Marks
Momentum = mass x velocity
Momentum = 75 x 3
Momentum = 225 kg m/s
1
Q
1
2
3
4
Velocity = momentum ÷ mass
Velocity = 720 ÷ 80
Velocity = 9m/s
2
1
2
Mass = momentum ÷ velocity
Mass = 4600 ÷ 15
Mass = 306.67kg
1
3
Momentum = mass x velocity
Momentum = 0.14 x 5
Momentum = 0.7 kg m/s
1
1
2