(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A particle of mass m is constrained to slide on the inside of a vertical smooth semi- circular ring of radius r. The position of the particle is described by a polar coordinate system whose origin is at the centre of the circle with axes along the orthogonal unit vectors r(hat) and θ(hat) where θ is the angle

Write down the resultant force acting on the particle as a function of θ.

2. Relevant equations

F=ma

3. The attempt at a solution

I have used the expression v = rθ(dot) to find that acceleration, a= rθ(double dot)θ(hat) −

v^2/r (rhat)

I'm having a problem getting the 'r' component of the accelration in terms of theta though, so that I can do F=ma(theta) to find resultant force.

Any help would be appreciated

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# Homework Help: Circular Motion using polar coordinates - Mechanics

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