A lead bullet at $27\,^oC$ just melts when stopped by an obstacle. Assuming that $25\%$ of heat is absorbed by the obstacle, then the velocity of the bullet at the time of striking ........ $m/s$ ( $M. P.$ of lead $= 327\,^oC,$ specific heat of lead $= 0.03\,cal/g\,^oC,$ latent heat of fusion of lead $= 6\,cal/g$ and $J = 4.2\,joule/cal$ )
$410$
$1230$
$307.5$
None of the above
Steam at $100\,^oC$ is passed into $22\,g$ of water at $20\,^oC$ The mass of water that will be present when the water acquires a temperature of $90\,^oC$ (Latent heat of steam is $540\,cal/g$) is ......... $\mathrm{g}$
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 ?
Compared to a burn due to water at $100\,^oC,$ a burn due to steam at $100\,^oC$ is
If the volume of a block of metal changes by $0.12\%$ when it is heated through $20^o\,C$, the coefficient of linear expansion (in per $^oC^{-1}$) of the metal is :-
The coefficient of apparent expansion of mercury in a glass vessel is $153\times 10^{-6}/\,^oC$ and in a steel vessel is $144\times 10^{-6}/\,^oC.$ If $\alpha $ for steel is $12 \times 10^{-6}/\,^oC,$ then $\alpha $ that of glass is