Question

heat is supplied to a system, but is internal energy does not increase.what is the process involved.

Answer 1

The process involved is isothermal(constant temperature)
as the internal energy depends on the change in temperature ,when in an isothermal process the heat supplied is totally taken up to do work.

Answer 2

Answer:

Isothermal process.

Explanation:

The answer is it is an Isothermal process. Because, when heat is supplied to a system and it's internal energy is not increasing, we can write the equation of First law of thermodynamics as

ΔQ = 0 + ΔW (Because, internal energy depends on change in temperature)

ΔQ =ΔW, i.e, the heat supplied is entirely used for doing work.

So, as the internal energy dosen't increases and  heat supplied is entirely used for doing work we can conclude that the process involved above is an Isothermal process.

Hope this is helpful.