Help Stuck on these 2 problems

1. Mar 16, 2005

joselyn

Help!!! Stuck on these 2 problems

1. Determine the motions equations of an ideal pendulum of mass m and lengh r.

2. A machine is formed by a homogenous cylinder of radio R and mass M. It rotates in its axel (frictionless). A mass by an inextensible cord (massless) is roller to cylinder. Find the motions equations.

2. Mar 16, 2005

Andrew Mason

This is fully explained in many texts. All you need to work out is the tangential restoring force on the pendulum mass:

$$F_{tang} = ma_{tang}$$ = tangential component of mg.

I am not sure I understand the problem here. Is the mass on a horizontal frictionless surface begin rolled toward the cylinder or is it rotating about the cylinder?

AM