There are two fixed heavy masses of magnitude `M` of high density at a distance `2d` apart. On the axis, a small mass `m` moves in a circle of radius `R` in the `y-z` plane between the heavy masses. Find the velocity of the small particle.

Explanation

To find the velocity of the small mass \( m \) moving in a circle of radius \( R \) between two fixed heavy masses \( M \) separated by a distance \( 2d \), we can follow these steps:

### Step 1: Analyze the Forces Acting on the Small Mass
The small mass \( m \) experiences gravitational forces due to both heavy masses \( M \). The net gravitational force will act downwards due to symmetry, as the horizontal components of the forces from both masses will cancel each other out.

### Step 2: Calculate the Gravitational Force
The gravitational force \( F \) exerted by one mass \( M \) on the small mass \( m \) can be expressed using Newton's law of gravitation:
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