Question

A system absorbs 12 J of heat from the surroundings; meanwhile, 28 J of work is done on the system. What is the change of the internal energy ΔEth of the system?

Answer 1

Answer: The value of change in internal energy of the system is, 40 J.

Explanation : Given,

Heat absorb from the surroundings = 12 J

Work done on the system = 28 J

First law of thermodynamic : It is a law of conservation of energy in which the total mass and the energy of an isolated system remains constant.

As per first law of thermodynamic,

`\Delta U=q+w`

where,

`\Delta U` = internal energy = ?

q = heat absorb from the surroundings

w = work done on the system

Now put all the given values in this formula, we get the change in internal energy of the system.

`\Delta U=12J+28J`

`\Delta U=40J`

Therefore, the value of change in internal energy of the system is, 40J.