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The mass ofa star is 3.98 xx 10^30 kg an...

The mass ofa star is `3.98 xx 10^30` kg and its radius is 106 km. It rotates.about its axis with an angular speed of `10^(-6)` rad/s. Calculate the speed of the star when it collapses to a radius of `10^4` km ? Assume the moment of inertia of the star to be `2/5 mr^(2)`.

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To solve the problem step by step, we will use the principle of conservation of angular momentum. The angular momentum of the star before and after its collapse must be equal since no external torques are acting on it. ### Step 1: Write the formula for angular momentum The angular momentum \( L \) of a rotating body is given by: \[ L = I \omega \] where \( I \) is the moment of inertia and \( \omega \) is the angular speed. ...
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