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oreosama
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Homework Statement
a small solid sphere of mass m and radius r starts from rest and rolls down a hill without slipping. the sphere encounters a loop of radius R where R >> r.
Given R determine the min height h such that the ball remains on the track throughout the loop
Homework Equations
I = 2/5 mR^2
ω = v/r
The Attempt at a Solution
highest point requiring most energy is at top of loop:
mgh = mg2R + 1/2 Iω^2
mgh = mg2R + 1/2 * 2/5 m r^2 *v^2/r^2
gh = 2Rg + 1/5*v^2
at top of loop, normal force is 0,
Fy = N + mg
ma = mg
m*v^2/R = mg
v^2 = gR
...
gh = 2Rg + 1/5 Rg
h = 11/5 R
this is correct?