A particle of mass m is suspended under gravity from a point of the ceiling by a light elastic string of natural length h. When it is in equilibrium the extension if the string is a. It is pulled down a further distance b, which is > a, and released. Show that when the string becomes slack the particle speed V is given by V^2 = g(b^2 – a^2)/a. Show that if b^2 > a(2h+a) it will hit the ceiling with a speed U given by U^2 = V^2 – 2gh.(adsbygoogle = window.adsbygoogle || []).push({});

Describe what happens i)if b<a, ii)if b>a, but b^2 < a(2h+a), iii) if b > a but the string is replaced by a spring

Any help would be great,

Thanks

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# Homework Help: Elastic String - help required

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