General
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Physics-

A plank is held at an angle  to the horizontal (Fig.) on two fixed supports A and B. The plank can slide against the supports (without friction) because of its weight Mg. Acceleration and direction in which a man of mass m should move so that the plank does not move.

Physics-General

  1. sin alpha open parentheses 1 plus straight m over straight M close parentheses
  2. g sin alpha open parentheses 1 plus M over m close parentheses text  up the incline  end text
  3. g sin alpha open parentheses 1 plus straight M over straight m close parentheses text  down the incline  end text
  4. g sin alpha open parentheses 1 plus m over M close parentheses text  up the incline  end text

    Answer:The correct answer is: g sin alpha open parentheses 1 plus straight M over straight m close parentheses text  down the incline  end text

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