Two blocks A and B of mass `m_A and m_B` respectively are kept in contact on a frictionless table. The experimenter pushes the block A from behind so that the blocks accelerate. If the block A exerts a fore F on the block B, what is the force exerted by the experimenter on A?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Identify the forces acting on the blocks
We have two blocks A and B with masses \( m_A \) and \( m_B \) respectively. The experimenter applies a force \( F' \) on block A. Block A exerts a force \( F \) on block B.

### Step 2: Write the equation of motion for the system
Since both blocks are in contact and on a frictionless surface, they will accelerate together. The total mass of the system is \( m_A + m_B \). The net force acting on the system is \( F' \), which causes the acceleration \( a \).

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