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A digital guide to the process of problem solving which highlights strengths and weaknesses, explains mistakes, reminds you about definitions and helps to clarify concepts. Check out our Introductory network to see it in action.


Explanation 1

When a car accelerates why does a helium balloon move backwards?


Circular motion 4

How fast does a pig fly?


Oscillations 3

What is the frequency of oscillation when a mass hangs on a spring?


Gravity 3

How far away are TV satellites?

Hot pages

  • KinematicsMechanics

    Before we can model motion we need to define the quantities that we are going to use, once that has been done we can investigate how they are related.

  • Distance and displacementMechanics

    Displacement as a vector, adding perpendicular displacements using pythagorus

  • Velocity and speedMechanics

    What is the difference between velocity and speed? When do we use instantaneous velocity and average velocity?

  • ForcesMechanics

    In an attempt to simplify we can consider all bodies to be a like a small ball with forces acting at the centre. Alternatively we could just consider the case of a small ball and ignore all other possibilities.

  • UnitsBasics

    There are 6 fundamental units we will use (not the candle) and a whole load of derived ones.