Two substances $A$ and $B$ of equal mass $m$ are heated at uniform rate of $6\,cal\,s^{-1}$ under similar conditions. A graph between temperature and time is shown in figure. Ratio of heat absorbed $H_A/H_B$ by them for complete fusion is

‘Stem Correction’ in platinum resistance thermometers are eliminated by the use of

Two thermometers $X$ and $Y$ have ice points marked at $15^o$ and $25^o$ and steam points marked as $75^o$ and $125^o$ respectively. When thermometer $X$ measures the temperature of a bath as $60^o$ on it, ..... $^oC$ would thermometer $Y$ read when it is used to measure the temperature of the same bath ?

Suppose there is a hole in a copper plate. On heating the plate, diameter of hole, would

A cylindrical rod with one end in a steam chamber and the outer end in ice results in melting of $0.1 \,\,gm$ of ice per second. If the rod is replaced by another with half the length and double the radius of the first and if the thermal conductivity of material of second rod is $1/4$ that of first, the rate at which ice melts is $gm/sec$ will be

Mercury is of ten used in clinical thermometers. Which one of the following properties of mercury is not a reason for this?