Laws of Motion - Result Question 54
54. A mass $m$ is attached to a thin wire and whirled in a vertical circle. The wire is most likely to break when:
[2014]
(a) the mass is at the highest point
(b) the wire is horizontal
(c) the mass is at the lowest point
(d) inclined at an angle of $60^{\circ}$ from vertical
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Answer:
Correct Answer: 54. (c)
Solution:
- (c) $T-mg=\frac{mv^{2}}{r}[$ centripetal force $]=\frac{mv^{2}}{r}$
$\Rightarrow T=mg+\frac{mv^{2}}{r}$
As the velocity is maximum at lowest point so tension is maximum at the lowest position of mass, so the chance of breaking is maximum.