What kind of friction come into play :
when a block of wood kept on cylindrical iron rods moves ?

Explanation

To determine the kind of friction that comes into play when a block of wood is placed on a moving cylindrical iron rod, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Scenario**:
- We have a cylindrical iron rod that is moving horizontally.
- A block of wood is placed on top of this moving rod.

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