List

Relative Motion

Take a message soldier
problem
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Take a message soldier

Age
14 to 18
Challenge level
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A messenger runs from the rear to the head of a marching column and back. When he gets back, the rear is where the head was when he set off. What is the ratio of his speed to that of the column?
Mach Attack
problem

Mach Attack

Age
16 to 18
Challenge level
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Have you got the Mach knack? Discover the mathematics behind exceeding the sound barrier.
Placeholder: several colourful numbers
problem

Bike

Age
16 to 18
Challenge level
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Calculate the paths of raindrops flying up from the back tyre of a bicycle