A 2.50 kg wheel has a diameter of 20.0 cm and is rotating at 3600 rpm. A force acts on it causing it to come to a rest in 10.0 seconds. What is the magnitude of the force?
Physics - Elena, Tuesday, November 27, 2012 at 9:26am
m=2.5 kg. R=D/2=0.1 m,
n₀=3600 rpm=3600/60=60 rev/s
t=10 s. F=?
2πn₀ = εt.
Newton’s 2 law for rotation:
If the wheel is disc I=mR²/2,
F=mRπn₀/t=2.5•0.1•3.14•60/10 = 4.71 N