(New tips are continually added to these pages. Check back in a few months' time for more)

TOPIC 1: Scalars and Vectors

Tip 1:

In Scalars, eg. distance, speed, you only have to consider the magnitude but not the direction.

But in Vectors, eg. displacement, velocity, you have to consider both the magnitude and the direction.

So if you walk 10km to the North, and 8km back South, the distance you have travelled is 18km (just add 10 + 8). But your displacement is 2km (10km - 8km), North (remember whenever you answer vector questions, you must include the direction otherwise marks will be deducted).

Another example, if you walk 3km North and then 4km East, the distance you have travelled is 7km (just add 3 + 4). But your displacement is 5km (Pythagora's Theorem), 53.13º East of North (or bearing of 53.13º).

Another example, if you were cycling at 20km/h towards the West, then turn around and cycle 30km/h towards the East, your speed has changed by 10km/h (just subtract 30 - 20). But your velocity has changed by 50km/h, (30 -(-20)), Eastward.