The radiation emitted by a star $A$ is $10,000$ times that of the sun. If the surface temperatures of the sun and the star $A$ are $6000 K$ and $2000 K$ respectively, the ratio of the radii of the star $A$ and the sun is
Medium
Download our appand 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
- 1View SolutionIn a closed room, heat transfer takes place by
- 2View SolutionColour of shining bright star is an indication of its
- 3The ratio of thermal conductivity of two rods of different material is $5 : 4$ . The two rods of same area of cross-section and same thermal resistance will have the lengths in the ratioView Solution
- 4Surface of the lake is at $2^{\circ} C$. The temperature of the bottom of the lake is ....... $^{\circ} C$View Solution
- 5View SolutionIf a black body is heated at a high temperature, it seems to be
- 6Bottom of a lake is at $0^{\circ} C$ and atmospheric temperature is $-20^{\circ} C$. If $1 cm$ ice is formed on the surface in $24 \,h$, then time taken to form next $1 \,cm$ of ice is ......... $h$View Solution
- 7A body cools from a temperature $3T$ to $2T$ in $10$ minutes. The room temperature is $T.$ Assume that Newton's law of cooling is applicable. The temperature of the body at the end of next $10$ minutes will beView Solution
- 8View SolutionIf the radius and length of a copper rod are both doubled, the rate of flow of heat along the rod increases ....... times
- 9A black body at a temperature of $1640 K$ has the wavelength corresponding to maximum emission equal to $1.75$ $\mu $. Assuming the moon to be a perfectly black body, the temperature of the moon, if the wavelength corresponding to maximum emission is $ 14.35$ $\mu $ is ...... $K$View Solution
- 10The top of a lake gets frozen at a place where the surrounding air is at a temperature of $-20\,^oC$. ThenView Solution