Question

when can you say that two systems are in thermodynamic equilibrium?

Answer 1

Answer:

when heat flow is absent b/w two system and are insulated

Answer 2

Explanation:

Thermodynamic equilibrium defines that the flow of heat stops when two stops are in contact with each other.

Zeroth law deals with the thermodynamic equilibrium which states that the heat flows from the high temperature to low temperature, But when systems stop the flow of temperature or heat means thermodynamic equilibrium is attained.

The required condition in zeroth law is that the systems must not separated by adiabatic wall otherwise the system not attending the thermodynamic equilibrium.