WorksheetsRadiation
Total questions: 10
Worksheet time: 5mins
How is the wavelength of radiation (λ) calculated, when propagation velocity (C) and frequency (ν) of the radiation is given
λ = C x ν
λ = C / ν
λ = ν / C
none of the above
A cavity with a small hole will always behave as a
White body
Transparent body
Black body
Opaque body
Reflectivity is defined as
Fraction of total energy transmitted by the body
Fraction of energy reflected by the body
Fraction of total energy absorbed by the body
Fraction of total energy absorbed and radiated by the body
When a surface absorbs a certain fixed percentage of striking radiation the surface is called
Grey body
Black body
White body
Opaque body
Which one is true regarding gases?
Reflectivity is unity
Absorptivity is zero
Reflectivity is zero
Transmissivity is zero
For a grey surface
Emissivity is constant
Absorptivity equals reflectivity
Emissivity equals transmissivity
Reflectivity equals emissivity
Which is true regarding radiation?
Radiation travels without any medium
Radiation travels only in medium
Radiation travels in medium but sometimes without medium
Radiation travels in medium or without medium
According to Stefan-Boltzmann law of thermal radiation
q = α A T5
q = α A T3
q = α A T4
q = α A T
