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KVPY2013PhysicsRotational Motion

A plank is resting on a horizontal ground in the northern hemisphere of the Earth at a 45^ latitude. Let the angular speed of the Earth be and its radius r_ e . The magnitude of the frictional force on the plank will be

Options

  1. Amr _ e ²
  2. Bmr _ e ² 2
  3. Cmr _ e ² 2
  4. DZero

Correct answer

C. mr _ e ² 2

Step-by-step solution

F ₅= m ² r 45^ where r= Rcos 45^ F _ r = m ² R 2

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