Two rods of same material have same length and area. The heat $\Delta Q$ flows through them for $12\, minutes$ when they are jointed in series. If now both the rods are joined in parallel, then the same amount of heat $\Delta Q$ will flow in ........ $\min$.

Solar radiation emitted by the sun resembles that emitted by a black body at a temperature of $6000\, K$. Maximum intensity is emitted at a wavelength of about $4800\,\mathop A\limits^o $. If the sun was cooled down from $6000\, K$ to $3000\, K$, then the peak intensity would occur at a wavelength of ......... $\mathop A\limits^o $

The maximum energy in the thermal radiation from a hot source occurs at a wavelength of $11 \times 10^{-5}\, cm$ . According to Wien's law, the temperature of the source (on kelvin scale) will be $n$ times the temperature of another source (on Kelvin scale) for which the wavelength at maximum energy is $5.5 \times 10^{-5}\, cm$ . The value of $n$ is

A body cools from $60\,^oC$ to $50\,^oC$ in $10\, minutes$. If the room temperature is $25\,^oC$ and assuming Newton's law of cooling to hold good, the temperature of the body at the end of the next $10\, minutes$ will be ....... $^oC$

The adjoining diagram shows the spectral energy density distribution $E_\lambda $ of a black body at two different temperatures. If the areas under the curves are in the ratio $16 : 1$, the value of temperature $T$ is  ......... $K$

Two rods having same area are used to connect two reservoirs at temperature $100\,^oC$ and $0\,^oC$ as shown. The temperature of junction is $70\,^oC$. If the rods are now interchanged, the temperature of junction will be  ......... $^oC$