Question : A stone of mass 𝑚 is tied to a string and is moved in a vertical circle of radius 𝑟 making 𝑛 revolutions per 𝑚𝑖𝑛𝑢𝑡𝑒. The total tension in the string when the stone is at its lowest point is
(A) 𝑚𝑔
(B) 𝑚(𝑔 +\pi nr^{2}
(C) 𝑚(𝑔 + 𝜋𝑛𝑟)
(D) 𝑚{𝑔 +\pi ^{2}\pi ^{2}\dfrac{r}{900}}
Answer : option (D)
Solution :
