- #1
songoku
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- Homework Statement
- A mass connected to one end of a rigid rod rotates at constant speed in a vertical plane about the
other end of the rod (please see below). The force exerted by the rod on the mass is
A. zero everywhere.
B. constant in magnitude.
C. always directed towards the centre.
D. a minimum at the top of the circular path.
- Relevant Equations
- centripetal force
(A) and (B) are obviously wrong but I think both (C) and (D) are correct.
At the top, the forces acting on the mass are tension and weight, both directed downwards so the equation of motion will be:
$$\text{Tension}+\text{Weight}=m.a$$
$$\text{Tension}=m.a-\text{Weight}$$
Based on that equation, tension will be minimum at the top position
But the direction of tension is always towards the center as the mass moves in circle.
Am I missing something?
Thanks