A stone tied to a string is rotated with a uniform speed in a vertical plane. If mass of the stone is m, length of the string is r and linear speed of the stone is v, then tension in the string when the stone is at its lowest point is

Question

A stone tied to a string is rotated with a uniform speed in a vertical plane. If mass of the stone is m, length of the string is r and linear speed of the stone is v, then tension in the string when the stone is at its lowest point is (A) mg (B) mv2 /r (C) (mv2 /r)-mg (D) (mv2/r)+mg

Tardigrade Admin · Accepted Answer

We know that centrifugal force =mv2/r When the stone is at the lowest point, then Tension in string = centrifugal force + weight of stone ∴ T=(mv2/r)+mg

Q. A stone tied to a string is rotated with a uniform speed in a vertical plane. If mass of the stone is $m$ , length of the string is $r$ and linear speed of the stone is $v$ , then tension in the string when the stone is at its lowest point is

$m g$

$m v^{2} / r$

$(m v^{2} / r) - m g$

$(m v^{2} / r) + m g$

We know that centrifugal force $= m v^{2} / r$

When the stone is at the lowest point, then Tension in string = centrifugal force + weight of stone

$∴ T = \frac{m v ^{2}}{r} + m g$

Q. A stone tied to a string is rotated with a uniform speed in a vertical plane. If mass of the stone is m, length of the string is r and linear speed of the stone is v, then tension in the string when the stone is at its lowest point is

mg

mv2/r

(mv2/r)−mg

(mv2/r)+mg