a)How many revolutios per minute must the apparatus shown in below figure make about a vertical axis so that the cord makes an angle of 450 with the vertical?b) What is the tension in the cord then. Given l = √2 m, a = 20 cm and m = 5 kg?

Dear J kiran

Diagram is not clear please upload it again and post your question

This type of problem can be solved by taking component of tension

T cos45 = mg

Tsin45 =mw²r    where r =lsin45

so T =mw²l

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