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Concepts Of Physics MCQ Edition [Volume 1]PhysicsNewton's Laws of Motion

Two blocks A and B having masses m_A and m_B respectively are placed in contact on a frictionless table. An experimenter pushes block A from behind, causing the blocks to accelerate. If the force exerted by block A on block B is F , determine the force applied by the experimenter on block A .

Options

  1. AF (1 + m_B m_A )
  2. BF (1 + m_A m_B )
  3. CF ( m_A m_B )
  4. DF ( m_B m_A )

Correct answer

B. F (1 + m_A m_B )

Step-by-step solution

Let the force applied by the experimenter be P . The blocks A and B move together with a common acceleration a . The equation of motion for block B is: F = m_B a a = F m_B The equation of motion for the system of blocks A and B is: P = (m_A + m_B) a Substituting the value of a we get: P = (m_A + m_B) ( F m_B ) P = F (1 + m_A m_B )

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