Answer
The main component of internal irrversibility in gear box is friction. Lubricating oil does not react with gear box matrial i.e. there is no chemical reaction as such inside gear box and gear box does not contain any gas. So, no irreversibility due to gas.
Work Step by Step
The main component of internal irrversibility in gear box is friction. Lubricating oil does not react with gear box matrial i.e. there is no chemical reaction as such inside gear box and gear box does not contain any gas. So, no irreversibility due to gas.