Question 101: Work, Energy and Power & Circular Motion

Question

A stone of mass m, tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string is

Accepted Answer

At any $$	heta :T - mg\cos 	heta  = {{m{v^2}} \over R}$$
$$ \Rightarrow T = mg\cos 	heta  + {{m{v^2}} \over R}$$
Since v is constant,
$$\Rightarrow$$ T will be minimum when cos$$	heta$$ is minimum.
$$\Rightarrow$$ $$	heta$$ = 180$$^\circ$$ corresponds to T
minimum
.

Answer

the same throughout the motion.

Answer

minimum at the highest position of the circular path.

Answer

minimum at the lowest position of the circular path.

Answer

minimum when the rope is in the horizontal position.

Work, Energy and Power & Circular Motion

A stone of mass m, tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string is

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