Question

Assertion (A): Zeroth law of thermodynamics gives us the concept of energy.
Reason (R): Internal energy is dependent on temperature.
1) Both Assertion and Reason are true and reason is the correct explanation of Assertion.
2) Both Assertion and Reason are true but reason is not the correct explanation of Assertion.
3) Assertion is true but reason is false.
4) Assertion is false but reason is true.

Answer 1

Hint:- Here we need to know all the three laws of thermodynamics, compare it with the assertion given in the question and also with the reason. Choose the correct option out of the four options given in the question.

Complete step-by-step solution:-
There are three basic laws in thermodynamics:
Zeroth Law of Thermodynamics: If a body”1” is in the thermal equilibrium with another body “2” and is also separately is in thermal equilibrium with the body“3”, then the bodies “2” and “3” will be in thermal equilibrium with each other.
First law of Thermodynamics: The first law of thermodynamics states that the change in the internal energy of a defined system is equal to the work done in the system in addition to the heat generated.
$\Delta U = Q + W$;
Here:
$\Delta U$= Change in internal energy.
$Q$= Heat.
W = Work Done.
Second law of Thermodynamics: In simple terms second law states that as the energy is transformed and transferred into another state and then another and then another, in this process more and more of it is wasted. It also states that any system in an isolated state has a tendency to degenerate itself into a more disordered state.
Here, in the question the assertion given is related to the first law but it is written as a Zeroth Law which is not true but the reason given is true.
Final Answer: Option “4” is correct. Assertion is true but reason is false.

Note:- Here we have to explain all the three laws of thermodynamics and then compare each law with the assertion and reasoning given in the question and choose the option that matches the appropriate option. Carefully compare the laws with the questions.