Who proposed the rate equation for convective heat transfer in 1701?

• A. Albert Einstein
• B. Sir Isaac Newton
• C. Daniel Bernoulli
• D. Sadi Carnot

Answer: (B)

Newton's law of cooling is the principle behind the convective heat transfer rate. It states that the rate at which heat is transferred by convection is proportional to the temperature difference between the surface and the surrounding fluid and to the surface area, written as dQ/dt = h A (T_s − T∞). This simple, foundational relation was proposed by Isaac Newton around 1701 after his studies of how bodies cool. It gives the intuition that hotter surfaces shed heat more quickly, and as they approach ambient temperature the rate slows. The other figures are associated with different ideas: Bernoulli with fluid dynamics and energy conservation in flowing fluids, Carnot with thermodynamic efficiency limits, and Einstein with relativity and quantum effects, not the basic convective rate law.