I'm having trouble with these two "classic meter stick problems"(adsbygoogle = window.adsbygoogle || []).push({});

1: A rod of length L and mass M stands vertically on a flat frictionless surface. A wad of putty of mass m and initial velocity v strikes the stick at a right angle at height 3/4 L. The collision is perfectly inelastic. Find the translational and rotational motions of the object.

2: A meter stick stands vertically at rest on a frictionless level surface. If it falls, what angular velocity will it have when it contacts the floor?

Heres what I've got, not sure where to go from here:

1: Momentum Initial = mv

Momentum final = (m+M)vf

L = mV x r = I w

Dont know what to do with the equations

2: I assumed a and alpha were constant, dont know if they are:

a = L/t^2 alpha = pi/t^2 L/a = pi/alpha

L w=pi v

w = pi * v / L

mg(L/2) = 1/2 mv^2 + 1/2 I w^2 >> I = 1/12 mR^2

gL = v^2 + 1/12L^2(pi * v/L)^2

v = (pi/L)sqrt(gL/(1+pi/12))

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# Homework Help: Rotational Motion Questions

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