A person is trying to ride a bike all the way round the inside of a pipe for a stunt in a film. The filmmaker wants to know what speeds are involved. The pipe has a diameter of 8 m. The mass of the bike and rider is 400 kg. The rider goes at a constant speed of 5 m/s. a) What is its acceleration at the bottom?
b) What is the force on the bike at an angle of 30° up from the bottom?
c) What is the minimum velocity at the top for the bike and rider to stay moving in a circle?
d) Do the bike and rider have sufficient velocity to stay movins a on a circle at the top?

1) The acceleration will be g = 9.8 m/s²

2) F = Wsinα = mgsinα = 400kg·9.8m/s²·1/2 = 2000N

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