3 Questions around this concept.
The Zeroth Law of Thermodynamics-
If two systems are in thermal equilibrium with a third system, they must be in thermal equilibrium with each other.
If system B is in thermal equilibrium with system A and system C is also in thermal equilibrium with system A, system B, and system C are in thermal equilibrium with each other.

A hot body has a higher temperature than a cold body. The temperature of two bodies decides the direction of heat flow when the two bodies are put in contact. The heat flows from the hot body to the cold body till the bodies are at the same temperature it is known as thermal equilibrium.
"Stay in the loop. Receive exam news, study resources, and expert advice!"
Among top 100 Universities Globally in the Times Higher Education (THE) Interdisciplinary Science Rankings 2026
Last Date to Apply: 29th April | Ranked #43 among Engineering colleges in India by NIRF | Highest Package 1.3 CR , 100% Placements
100% Placement Assistance | Avail Merit Scholarships | Highest CTC 43 LPA
Last Date to Apply: 26th April | NAAC A++ Accredited | NIRF Rank #3
Application Deadline: 15th April | Recognized as Institute of Eminence by Govt. of India | NAAC ‘A++’ Grade | Upto 75% Scholarships
World-class and highly qualified engineering faculty. High-quality global education at an affordable cost
Explore on Careers360
Student Community: Where Questions Find Answers