1. Doubling the resultant force doubles the acceleration
Force , mass and acceleration
a = 2 m/s/s
2 N
1 Kg
Doubling the resultant force doubles the acceleration
Acceleration  Resultant Force
a  F
or F = ma

2. a = 30 m/s/s
1200Kg
F = ma
F = x 30
F = N

3. Use Force = mass x acceleration
to calculate the resultant force on
these objects :
Use acceleration = resultant force
mass
to calculate the acceleration of
these objects : Q1 Q5
A ball of mass 2Kg
accelerates at 3 m/s/s
20Kg
2 x 3 = 6 N
40 / 20 = 2 m/s/s Q2
A truck of mass 2000Kg
accelerates at 2 m/s/s Q6
2000 N
3000 N
2000 x 2 = 4000 N
2000 Kg
1000 / 2000 = 0.5 m/s/s Q3
A helicopter of mass 3000Kg
accelerates at 4 m/s/s Q7
3000 x 4 = N
2Kg Q4
A rugby ball of mass 2Kg
accelerates at 5 m/s/s
2 x 5 = 10 N
8 / 2 = 4 m/s/s

4. Force, mass and acceleration
A force of 1000N is applied to push a mass of 500kg. How quickly does it accelerate? m/s/s
A force of 3000N acts on a car to make it accelerate by 1.5m/s2. What is the mass of the car?
……………….Kg
3) A car accelerates at a rate of
5m/s2. If its mass is 500kg how
much driving force is the engine
applying? ………………N
4) A force of 10,000N is applied to a
boat of mass 20,000kg mass. How
much does it accelerate by?
………………………m/s2 F A M

5. Force, mass and acceleration
A force of 1000N is applied to push a mass of 500kg. How quickly does it accelerate? m/s/s
A force of 3000N acts on a car to make it accelerate by 1.5m/s2. What is the mass of the car?
……………….Kg
3) A car accelerates at a rate of
5m/s2. If its mass is 500kg how
much driving force is the engine
applying? ………………N
4) A force of 10,000N is applied to a
boat of mass 20,000kg mass. How
much does it accelerate by?
………………………m/s2 Q1
F = m a
F = a m
1000 = a
500
2 m/s2 = a F A M

6. Force, mass and acceleration
A force of 1000N is applied to push a mass of 500kg. How quickly does it accelerate? m/s/s
A force of 3000N acts on a car to make it accelerate by 1.5m/s2. What is the mass of the car?
……………….Kg
3) A car accelerates at a rate of
5m/s2. If its mass is 500kg how
much driving force is the engine
applying? ………………N
4) A force of 10,000N is applied to a
boat of mass 20,000kg mass. How
much does it accelerate by?
………………………m/s2 Q2
F = m a
F = m a
3000 = m
1.5
2000 Kg = m F A M

7. Force, mass and acceleration
A force of 1000N is applied to push a mass of 500kg. How quickly does it accelerate? m/s/s
A force of 3000N acts on a car to make it accelerate by 1.5m/s2. What is the mass of the car?
……………….Kg
3) A car accelerates at a rate of
5m/s2. If its mass is 500kg how
much driving force is the engine
applying? ………………N
4) A force of 10,000N is applied to a
boat of mass 20,000kg mass. How
much does it accelerate by?
………………………m/s2 Q3
F = m a
F = m a
F = 500 x 5
F = 2500 N F A M

8. Force, mass and acceleration
A force of 1000N is applied to push a mass of 500kg. How quickly does it accelerate? m/s/s
A force of 3000N acts on a car to make it accelerate by 1.5m/s2. What is the mass of the car?
……………….Kg
3) A car accelerates at a rate of
5m/s2. If its mass is 500kg how
much driving force is the engine
applying? ………………N
4) A force of 10,000N is applied to a
boat of mass 20,000kg mass. How
much does it accelerate by?
………………………m/s2 Q4
F = m a
F = a m
10000 = a
20000
0.5 m/s2 = a F A M

9. Experiment to investigate how force effects acceleration
Interrupt card to
compute acceleration
Light gate connected
to computer 1N
1 Kg
The force caused
by gravity on 100g
mass is = 1N
Assume there is no friction today!

10. Acceleration
( m/s/s )
Force
( N )
Acceleration
( m/s/s ) 1
0.5 2
1.0
2.5
1.5 3
2.0 4
2.0 5
1.5
2.5
1.0
0.5 1 2 3 4 5
Force
( N )

11. For constant mass Conclusions: Acceleration ( m/s/s ) Force ( N )1
0.5 2
1.0
2.5
1.5 3
2.0 4
2.0 5
1.5
2.5
1.0
0.5
Conclusions: 1 2 3 4 5
Force
( N )

12. * the acceleration nearly increases in direct proportion to the force
( m/s/s )
Force
( N )
Acceleration
( m/s/s )
For constant mass 1
0.5 2
1.0
2.5
1.5 3
2.0 4
2.0 5
1.5
2.5
1.0
0.5
Conclusions:
* the acceleration nearly increases
in direct proportion to the force
( if the force doubles so
does the acceleration ) 1 2 3 4 5
Force
( N )
Why nearly?

13. * the 1/acceleration increases in direct proportion to the mass
( s2/m )
Mass
( Kg )
Acceleration
( m/s/s )
1/acceln
( s2/m )
For constant force 1
4.0
0.25 2
2.0
0.50
2.00 3
1.5
0.75
1.00 4
1.0
1.0 5
0.5
2.0
0.75
0.50
Conclusions:
* the 1/acceleration increases
in direct proportion to the mass
( if the mass doubles the acceleration
halves, and
1/acceln increases in direct proportion.
0.25 1 2 3 4 5
Mass
( kg)

20. Acceleration
( m/s/s )
Force
( N )
Acceleration
( m/s/s ) 1
0.5 2
1.0
2.5
1.5 3
2.0 4
2.0 5
1.5
2.5
1.0
Conclusions:
0.5 1 2 3 4 5
Force
( N )

21. 1/ acceleration
( s2/m )
Mass
( Kg )
Acceleration
( m/s/s )
1/acceln
( s2/m ) 1
4.0
0.25 2
2.0
0.50
2.00 3
1.5
0.75
1.00 4
1.0
1.0 5
0.5
2.0
0.75
0.50
Conclusions:
0.25 1 2 3 4 5
Mass
( kg)