An ideal black body at room temperature is thrown into a furnace. It is observed that
  • A
    Initially it is the darkest body and at later times the brightest
  • B
    It is the darkest body at all times
  • C
    It cannot be distinguished at all times
  • D
    Initially it is the darkest body and at later times it cannot be distinguished
IIT 2002, Medium
art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    Aring consisting of two parts $ADB$ and $ACB$ of same conductivity $k$ carries an amount of heat $H$. The $ADB$ part is now replaced with another metal keeping the temperatures $T_1$ and $T_2$ constant. The heat carried increases to $2H$. What $ACB$ should be the conductivity of the new$ADB$ part? Given $\frac{{ACB}}{{ADB}}= 3$
    View Solution
  • 2
    The sun emits a light with maximum wavelength $510\, mm$ while another star $X$ emits a light with maximum wavelength of $350\, nm$. What is the ratio of surface temperature of sun and the star $X$
    View Solution
  • 3
    Three rods of identical cross-section and lengths are made of three different materials of thermal conductivity $K _{1}, K _{2},$ and $K _{3}$, respectively. They are joined together at their ends to make a long rod (see figure). One end of the long rod is maintained at $100^{\circ} C$ and the ther at $0^{\circ} C$ (see figure). If the joints of the rod are at  $70^{\circ} C$ and $20^{\circ} C$ in steady state and there is no loss of energy from the surface of the rod, the correct relationship between $K _{1}, K _{2}$ and $K _{3}$ is 
    View Solution
  • 4
    Air is bad conductor of heat or partly conducts heat, still vacuum is to be placed between the walls of the thermos flask because
    View Solution
  • 5
    Two rectangular blocks, having identical dimensions, can be arranged either in configuration $I$ or in configuration $II$ as shown in the figure. One of the blocks has thermal conductivity $k$ and the other $2k$. The temperature difference between the ends along the $x-$ axis is the same in both the configurations. It takes $9s$ to transport a certain amount of heat from the hot end to the cold end in the configuration $I$. The time to transport the same amount of heat in the configuration $II$ is .......... $\sec$
    View Solution
  • 6
    The Wien’s displacement law express relation between
    View Solution
  • 7
    The temperatures of two bodies $A$ and $B$ are respectively ${727^o}C$ and ${327^o}C$. The ratio ${H_A}:{H_B}$ of the rates of heat radiated by them is
    View Solution
  • 8
    As per the given figure, two plates $A$ and $B$ of thermal conductivity $K$ and $2 K$ are joined together to form a compound plate. The thickness of plates are $4.0 \,cm$ and $2.5 \,cm$ respectively and the area of cross-section is $120 \,cm ^{2}$ for each plate. The equivalent thermal conductivity of the compound plate is $\left(1+\frac{5}{\alpha}\right) K$, then the value of $\alpha$ will be_______
    View Solution
  • 9
    A black body is heated from ${27^o}C$ to ${127^o}C$. The ratio of their energies of radiations emitted will be
    View Solution
  • 10
    The temperature of a liquid drops from $365K$ to $361 K$ in $2$ minutes. Find the time during which temperature of the liquid drops from $344\;K$ to $342K$. Temperature of room is $293\;K$  ....... $\sec$
    View Solution