1. Force & Motion
Terms and Symbols

2. What do you think you know about force and motion?

3. Force and Motion Terms
Term
Definition
Picture/Equation

4. Force & Motion Force - a push or pull on an object
Position – an object’s location
Motion – the act of changing position
Distance - measure of how far an object moves in relation to a reference point; the amount of change in position
D = Xf – Xi (final position – initial position)

5. Frame of reference – the context by which we observe objects (reference point)
Reference point- the object that appears to stay in place or an arbitrary point on an object used to establish position
Example: sitting on the beach watching a boat go by. The boat is moving relative to your position on the beach

6. D ÷ S T X Speed the distance an object travels in a unit of time.
The symbols for speed:
v for velocity
r for rate
s for speed
S = D/T
The unit of speed is distance per unit of time.
For example: 50 km/h or 5 m/s D S T ÷ X

7. V Velocity A measure of an object’s speed in a certain direction
for example: 50 km/h west or 5 m/s west V
Speed Direction

8. Acceleration the rate at which velocity changes over time
an object accelerates if its speed, direction, or both change
Increase in acceleration = positive acceleration
Decrease in acceleration = negative acceleration or deceleration

9. xf – final position x – position xi – initial position SYMBOLS
- delta – means change
d – distance
x – position
x – change in position
xi – initial position
xf – final position

10. Displacement Time Interval
a measure of how far an object moves in a certain direction
(for example: 140 km west)
Time Interval
how long it takes for something to happen.