An object moves in a vertical circle of radius R; the object is constrained to m
ID: 1585874 • Letter: A
Question
An object moves in a vertical circle of radius R; the object is constrained to move in a circle by a string attached to the object on one end and a frictionless anchor on the other end. The object was set in motion at some initial time and now circles under the influence of only the force due to gravity and any forces exerted on it by the string; its angular velocity is not constant. When the object is at the location indicated, with the string horizontal, what is the magnitude of the tangential acceleration of the mass?
A. g/2 B. 2g C. mg/R D. g E. We can't say this without knowing the speed of the mass.
Explanation / Answer
We know F(centripital)=mv2/r.
When string is horizontal ,Tension is behave like centripital force..
Untill value of velocity ,is not provided.we cannot find Tension.
Option E.