A car goes around a vertical circle (Uniform Circular Motion)

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Chandasouk
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Homework Statement




A small remote-control car with a mass of 1.51 kg moves at a constant speed of v = 12.0 m/s in a vertical circle inside a hollow metal cylinder that has a radius of 5.00 m.

yf_Figure_05_76.jpg



What is the magnitude of the normal force exerted on the car by the walls of the cylinder at point A (at the bottom of the vertical circle)?

What is the magnitude of the normal force exerted on the car by the walls of the cylinder at point B (at the top of the vertical circle)?


Do I utilize Fnet = ma which would give me 43.488N as Fnet, but I do not see how that would help? I don't know what to do.
 
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Try drawing a force diagram when the car in at the bottom of the cylinder and when its
at the top of the cylinder.
 
For Part A, it would just be Fn pointing up and w pointing down.

w=mg so (1.51kg)(-9.8) = -14.798N so Fn must be 14.798N ?


Would part B basically be the same?
 
F_y = m*a_y
a_y = v^2/r

Does that help?
 
For part A it should be N - mg = 0, right ? Since mg is pointing down thus N has to be
pointing up.

For part B its not quite the same.