Emissive and Absorptive Power
Trending Questions
- the maximum intensity radiation will be at frequency 2vm
- the maximum intensity radiation will be at frequency 12vm
- the total emitted energy will increase by a factor 16
- the total emitted energy will increase by a factor 2
- 81E
- 3E
- E3
- E81
The rate of radiation of a black body at 0o C is E J/sec. The rate of radiation of this black body at 273o C will be
A point source of heat of power is placed at the center of a spherical shell of mean radius . The material of the shell has thermal conductivity . If the temperature difference between the outer and the inner surface of the shell is not to exceed ., then the thickness of the shell should not be less than
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/8941/content_218.png)
Stefen's constant σ=5.67×10−8 W m−2K−4
- 0.412×10−5 m2
- 0.918×10−4 m2
- 0.212×10−4 m2
- 0.416×10−4 m2
- 4/1
- 1/4
- 16/1
- 1/16
Ice at –20° C is added to 50 g of water at 40°C. When the temperature of the mixture reaches 0°C, it is found that 20 g of ice is still not melted. The amount of ice added to the water was close to
(Specific heat of water = 4.2 J/g/°C)
Specific heat of Ice = 2.1 J/g/°C
The heat of fusion of water at 0°C = 334 J/g)
50 g
40 g
60 g
100 g
![](https://search-static.byjusweb.com/question-images/byjus/ckeditor_assets/pictures/962832/original_Screenshot_2020-12-24_212503.png)
- ex>ey and ax<ay
- ex<ey and ax>ay
- ex>ey and ax>ay
- ex<ey and ax<ay
The temperature of 170g of water at is lowered to by adding certain amount of ice to it. Find the mass of the ice added.
(Given: Specific heat capacity of water and specific latent heat of ice)
- n=1→n=4
- n=2→n=4
- n=2→n=5
- n=2→n=3
If wavelengths of maximum intensity of radiations emitted by the sun and the moon are 0.5×10−5 m and 10−4 m respectively, the ratio of their temperatures is
1/100
1/200
100
200
- at different temperatures
- at same temperature
- two surfaces at same temperature and two at different temperature
- three surfaces at same temperature and one at different temperature
- 0.52
- 0.48
- 0.64
- 0.36
The rate of radiation of a black body at 00 C is EJ/sec. The rate of radiation of this black body at 2730 C will be
16 E
E
8 E
4 E
- 300 W
- 209 W
- 250 W
- 400 W
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/649175/original_Q6.png)
- 15 min
- 5 min
- 30 min
- 60 min
- eλ=aλ=Eλ
- eλ=aλEλ
- eλaλEλ=constant
- aλeλ=12Eλ
- 12Q
- 14Q
- 2Q
- 4Q
- 600 W
- 300 W
- 900 W
- 1200 W
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1337690/original_1.png)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1337693/original_1%28i%29.png)
- The internal resistance of battery is 0.2 Ω.
- The emf of battery is 2 V
- R at which power is 5 W is 2.5 Ω
- At i = 2 A, power is 3.2 W
Two spheres P and Q, of same colour having radii 8 cm and 2 cm are maintained at temperatures 127o C and 527o C respectively. The ratio of energy radiated by P and Q is
0.054
0.0034
1
2
If denotes coefficient of thermal conductivity, the density and the specific heat, the unit of , where will be,
![](https://search-static.byjusweb.com/question-images/byjus/ckeditor_assets/pictures/1022817/original_109.png)
- 3
- 1/√3
- 1/3
- √3
- 5000 J
- 1000 J
- 9000 J
- 900 J