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  4. A heavy particle is suspended by a string of length 60 cm from a fixed point O. It is projected horizontally with speed 4.2 m / s from its lowest position: (Take g=9.8 m / s 2 )

Q. A heavy particle is suspended by a string of length $60\, cm$ from a fixed point $O$. It is projected horizontally with speed $4.2\, m / s$ from its lowest position: (Take $g=9.8\, m / s ^{2}$ )

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Solution:

The minimum speed requierd to complete the circular motion is $(5 g l)^{1 / 2}=5.42 \,m / s$ which is more than the imparted speed so particle will not be able to attain the maximum height due to the initial speed which is $v^{2} / 2 g=90\, m$. The string will slack before it reaches thê 90 height abovee thê initial point.

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