Question

Explain what is Newton's law of cooling .Why its graph ( temperature vs time ) is a curve not a straight line or anything else

Answer 1

According to Newton's law of cooling, "the rate of heat loss of a body is proportional to the difference in temperatures between the body and its surroundings."

Its graph is a curve not a straight line or anything else because the slope of the tangent to the curve at any point gives the rate of fall of temperature. If rate of fall of temperature is plotted against excess temperature, we get a straight line passing through the origin.