A body is suspended from a smooth horizontal nail by a string of length 0.25 metre. What minimum horizontal velocity should be given to it in the lowest position so that it may move in a complete vertical circle with the nail at the centre?

Question

A body is suspended from a smooth horizontal nail by a string of length 0.25 metre. What minimum horizontal velocity should be given to it in the lowest position so that it may move in a complete vertical circle with the nail at the centre? (A)  √12.25 ms-1 (B)  4.9 ms-1 (C)  7√2 ms-1 (D)  √9.8 ms-1

Tardigrade Admin · Accepted Answer

When a string fixed with a nail, moves along a vertical circle, then the minimum horizontal velocity at the lowest point of circle is given by v =√5 rg =√5 × 0.25 × 9.8 =√12.25 m / s

Q. A body is suspended from a smooth horizontal nail by a string of length $0.25$ metre. What minimum horizontal velocity should be given to it in the lowest position so that it may move in a complete vertical circle with the nail at the centre?

$12.25 m s^{- 1}$

$4.9 m s^{- 1}$

$72 m s^{- 1}$

$9.8 m s^{- 1}$

When a string fixed with a nail, moves along a vertical circle, then the minimum horizontal velocity at the lowest point of circle is given by
$v = 5 r g = 5 \times 0.25 \times 9.8$
$= 12.25 m / s$

Q. A body is suspended from a smooth horizontal nail by a string of length 0.25 metre. What minimum horizontal velocity should be given to it in the lowest position so that it may move in a complete vertical circle with the nail at the centre?

12.25​ms−1

4.9ms−1

72​ms−1

9.8​ms−1