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In a rotor, a hollow vertical cylindrical structure rotates about its axis and a person rests against the inner wall. At a particular speed, the floor below the person is removed and the person hangs resting against the wall without any floor. If the radius of the rotor is 2   m and the coefficient of static friction between the wall and the person is 0 . 2 , find the minimum speed (in m   s - 1 ) of any po

Correct answer

10

Step-by-step solution

The situation is shown in the diagram When the floor is removed, the forces on the person are (1) weight mg downward (2) normal force N due to the wall, towards the centre (3) frictional force f s , parallel to the wall, upward. The person is moving in a circle with a uniform speed, so its acceleration is v 2 r towards the centre. Newton's law for the horizontal direction (2nd law) and for the vertical direction (1st law) give N = mv 2 / r ...(i) and f s = mg . ...(ii) ​For the minimum speed when the floor may be r

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