In the figure given in the text if mass of the rod is `m` then find hinge force.
(a). Just after the rod is released from the horizontal position.
(b). When rod becomes vertical

Explanation

To solve the problem of finding the hinge force on a rod of mass \( m \) at two different positions (just after it is released from the horizontal position and when it becomes vertical), we will break down the solution into two parts.

### Part (a): Hinge Force Just After the Rod is Released from the Horizontal Position

1. **Identify Forces Acting on the Rod**:
- The weight of the rod \( mg \) acts downward at its center of mass, which is at a distance \( \frac{L}{2} \) from the hinge.
- The hinge exerts a force \( R \) on the rod, which has both vertical and horizontal components.

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