Two trains set off at the same time from each end of a single
straight railway line. A very fast bee starts off in front of the
first train and flies continuously back and forth between the two
trains. How far does Sidney fly before he is squashed between the
A security camera, taking pictures each half a second, films a
cyclist going by. In the film, the cyclist appears to go forward
while the wheels appear to go backwards. Why?
How far have these students walked by the time the teacher's car
reaches them after their bus broke down?
They set off towards one another at 10 metres/second.
Just at that moment, a fly sitting on the front of one of the
engines sets off and starts to fly along the railway line at 25
The fly eventually meets the front buffer of the other engine
which by now has travelled some way along the track.
The fly immediately turns round and flies at its usual speed
towards the first engine.
When it gets there it turns round again and flies back towards
the other engine, and so on, and so on...
How far will the
fly have travelled before the unhappy end?
Can you alter the distance or the speeds to change the