A. Krichoff’s law
B. Stefan’s law
C. Wien’ law
D. Planck’s law
E. Black body law
Related Mcqs:
- According to Kirchoff’s law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a _________________?
A. grey body
B. brilliant white polished body
C. red hot body
D. black body
E. none of the above - The emissive power of a body depends upon its___________________?
A. temperature
B. wave length
C. physical nature
D. all of the above
E. none of the above - If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of___________________?
A. 3
B. 6
C. 9
D. 27
E. 81 - The value of the wavelength for maximum emissive power is given by ___________________?
A. Wien’s law
B. Planck’s law
C. Stefan’s law
D. Fourier’s law
E. Kirchhoff’s law - Emissivity of a white polished body in comparison to a black body is________________?
A. higher
B. lower
C. same
D. depends upon the shape of body
E. none of the above - The total emissivity power is .defined as the total amount of radiation emitted by a black body per unit_______________?
A. temperature
B. thickness
C. area
D. time
E. area and time - All radiations in a black body are___________________?
A. reflected
B. refracted
C. transmitted
D. absorbed
E. partly reflected and partly absorbed - A perfect black body is one which_______________?
A. is black in colour
B. reflects all heat
C. transmits all heat radiations
D. abslprbs heat radiations of all wave lengths falling on it
E. fully opaque - According to Stefan’s law, the total radiation from a black body per second per unit area is proportional to____________________?
A. absolute temperature
B. T2
C. T5
D. t
E. l/T - Depending on the radiating properties, a body will be black when_________________?
A. p = 0, x = 0 and a = 1
B. p= l,T = 0anda = 0
C. p = 0, x = 1 and a = 0
D. x = 0, a + p = 0
E. a = 0,x + p= 1.
where a = absorptivity, p == reflectivity, X = transmissivity
