Two metallic spheres ${S_1}$ and ${S_2}$are made of the same material and have identical surface finish. The mass of ${S_1}$ is three times that of ${S_2}$. Both the spheres are heated to the same high temperature and placed in the same room having lower temperature but are thermally insulated from each other. The ratio of the initial rate of cooling of ${S_1}$ to that of ${S_2}$ is
$1/3$
${(1/3)^{1/3}}$
$1/\sqrt 3 $
$\sqrt 3 /1$
Certain quantity of water cools from $70^o C$ to $60^o C$ in the first $5$ minutes and to $54^o C$ in the next $5$ minutes. The temperature of the surroundings is ..... $^oC$
Are rate of heat emission and rate of cooling same ? Explain this.
Equal masses of two liquids are filled in two similar calorimeters. The rate of cooling will
A body takes $10$ minutes to cool down from $62^o C$ to $50^o C$. If the temperature of surrounding is $26^o C$ then in the next $10$ minutes temperature of the body will be ......... $^oC$
According to Newton’s law of cooling, the rate of cooling of a body is proportional to ${(\Delta \theta )^n}$, where $\Delta \theta $ is the difference of the temperature of the body and the surroundings, and n is equal to