Physics-
General
Easy

Question

A insect crawls up a hemispherical surface very slowly (see the figure). The coefficient of friction between the surface and the insect is 1 third  . If the line joining the centre of the hemispherical surface to the insect makes an angle a with the vertical, the maximum possible value of  alpha is given :

  1. cot alpha equals 3
  2. tan alpha equals 3
  3. sec alpha equals 3
  4. cosec alpha equals 3

The correct answer is: cot alpha equals 3

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