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Today Puzzle #605

Puzzle No. 605– Wednesday 6 November

Today is ‘This is Engineering Day’, so today’s puzzle is an engineering one. A parent has purchased a vertical loop the loop track for a toy car. Assuming the track and car are frictionless, how much higher than the top of the loop the loop must the car start in order for it to go round without falling off?

Today’s #PuzzleForToday has been set by Dr Shaun Fitzgerald, Director of the Royal Institution and Dr Hugh Hunt, Reader in Engineering at Cambridge University.

Click here for the answer

Total height needed is 2.5 times the radius, so the car needs to start 0.5 radii above the top of the loop the loop.

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