A metal surface is illuminated by light of frequency $2 imes 10^{15}$ Hz. The work function of the metal is $5$ eV. Which of the following statements is correct regarding the emission of photoelectrons?

Newton’s law of cooling is a special case of

There are two spherical balls $A$ and $B$ of the same material with same surface, but the diameter of $A$ is half that of $B$. If $A$ and $B$ are heated to the same temperature and then allowed to cool, then

A calorimeter filled with hot water cools from ${60^{\rm{o}}}C\,\,\,to\,\,\,{50^{\rm{o}}}C$ in 4 min and ${40^{\rm{o}}}C\,\,\,to\,\,\,{30^{\rm{o}}}C$  in 8 min. The temperature of surrounding is

A liquid cools down from ${70^0}C$ to ${60^0}C$ in 5 minutes . The time taken to cool it from ${60^0}C$ to ${50^0}C$ will be

A body initially at ${80^0}C$ cools to ${64^0}C$ in 5 min and to ${52^0}C$ in 10 min. the temperature of the surrounding is

Hot water kept in a beaker placed in a room cools from ${70^0}C$ to ${60^0}C$ in 4 minutes. The time taken by it to cool from ${69^0}C$ to ${59^0}C$ will be

Which of the following statements is true/correct

A container contains hot water at ${100^0}C$. If in time ${T_1}$ temperature falls to ${80^0}C$ and in time ${T_2}$ temperature falls to ${60^0}C$ from ${80^0}C$, then

A body takes 10 minutes to cool from ${60^0}C\,to\,\,{50^0}C$ .The temperature of surroundings is constant at ${25^0}C$. Then, the temperature of the body after next 10 minutes will be approximately

Two spheres of radii in the ratio 1:2 and densities in the ratio 2:1 and of same specific heat, are heated to same temperature and left in the same surrounding. Their rate of cooling will be in the ratio