Two cylinders A and B of equal capacity are connected to each other via a stop cock. A contains an ideal gas at standard temperature and pressure. B is completely evacuated. The entire systems is thermally insulated. The stop cock is suddenly opened. The Process is :

In which of the following processes, heat is neither absorbed nor released by a system?

Increase in tempertaure of a gas filled in a container would lead to :

The efficiency of an ideal heat engine working between the freezing point and boiling point of water, is