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2.1. Motion

At GCSE we were happy with speed = distance/ time - an equation that is very useful when we talk about movement at a CONSTANT SPEED. If something is  accelerating, that equation is less useful. 

Now, at IB we start thinking about movement with CONSTANT ACCELERATION. For this, we have a set of equations you probably know as the SUVAT equations.

 

Displacement, Velocity and Acceleration

To start off with, we need to make sure we are confident with the various concepts of displacement, velocity and acceleration (and their scalar equivalents). If you need a bit of a recap, flick back to the section on vectors (particularly resolving, addition and subtraction). 

 

Motion Graphs

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PHET have two nice simulations that help with this. 

1) Calculus Grapher (requires Flash, so try Edge rather than Chrome)

- Ensure integral and derivative are ticked. Now the top graph illustrates displacement, the middle velocity and the bottom acceleration. Try out different shapes and work out how the others change.

2) The Moving Man

- The 'Charts' tab is most useful. Move the man at a constant speed/ accelerating and compare displacement, velocity and acceleration.

 

SUVAT Equations

There are 5 of these SUVAT equations.

 

Projectile Motion

Once you are completely confident with your SUVAT and have had some practice, we can start looking at motion in two dimensions, projectiles. 

Additional Resources

 

Once you are completely confident with your SUVAT and have had some practice, we can start looking at motion in two dimensions, projectiles.