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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

  • Circular motionCircular motion and Gravity

    If your speed is constant how can you be accelerating. When you move in a circle it feels like you are being thrown out so how come the force is towards the centre? If too many people join me on a roller coaster will we all fall to our death

  • 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.

  • Wave basicsOscillations and Waves

    Wave quantities wave propagation reflection refraction interference diffraction