P4 Twenty First Century Science

The SPEED of an object is explained using an equation, yes maths, we have to do maths in science! :(

The SPEED equation is... SPEED = DISTANCE ÷ TIME... REMEMBER THIS!

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The unit we use for SPEED is m/s. METERS PER SECOND. eg. 20 m/s, 43 m/s.

Other Units we SHOULD use:

Weight = N (Newtons)

Mass = KG (Kilograms)

Energy = J (Joules)

REMEMBER: ALWAYS put these at the end of your answers on a test paper! Marks could be lost :'(

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Velocity! Don't mistake this for speed, they are NOT the same.

Velocity is the speeeeed of something but in a CERTAIN direction.

Heres a lovely example: 

If you are running at 5 m/s in a NORTHELY direction but you turn to a WESTERNLY direction, your speed is constant but your VELOCITY is CHANGING, because you changed direction.

Velocity...speed but in a certain direct.

Speed... Just how fast you are going in any direction.

LOOK, heres an example of a VELOCITY TIME GRAPH! There always fun. http://www.answers.com/topic/velocity-time-graph

Average speed, how do we work this out!?

Well use the same equation as before.. AVERAGE SPEED = DISTANCE ÷ TIME.

Again, an amazing example:

If a monkey is runs 100m in 30s. What is the average speed?

3.33 m/s. SIMPLES, always bring a calculator to an exam, very very very very important.

Use this website, Bitesize... heres the link for this module. http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr/explaining_motion/