Question

Two blocks of steel, the first of mass 1 kg and the second of mass 2 kg, are in thermal equilibrium with a third block of aluminum of mass 2kg that has a temperature of 400 K. What are the respective temperatures of the first and second steel blocks? 

(A) 400 K and 200 K 

(B) 200 K and 400 K 

(C) 400 K and 400 K 

(D) 800 K and 400 K 

(E) None of the above

Answer 1

Correct option (C) 400 K and 400 K

Being in thermal equilibrium means the objects are at the same temperature. Mass is irrelevant. The question describes the zeroth law of thermodynamics.