Perfect Black Bodies And Radiation (physics Only) (GCSE Physics)

Wien’s displacement idea (qualitative) says the peak wavelength of black-body radiation is inversely proportional to temperature. Which sentence matches that law?

If a black body’s absolute temperature is 290 K, the peak of its emitted spectrum is about 10 micrometres (µm). If its temperature were raised to 580 K (double), the peak would be about

Which surface behaves most like an ideal black body for infrared radiation?

Kirchhoff’s law of thermal radiation (simple form) states: at thermal equilibrium, the emissivity of a body equals its absorptivity at each wavelength. This implies that

A perfect black body is best defined as an object that

Which statement about selective emitters is correct?

If two objects at the same absolute temperature are placed near each other, a perfect black body among them will

If a body has emissivity e and temperature T, the total emitted power per unit area = esT4. If T doubles and e stays same, emitted power changes by factor

Which real object is closest in behaviour to a perfect black body in the infrared region?

For a grey body with emissivity 0.5 at temperature 600 K, and s the Stefan–Boltzmann constant, the emitted power per unit area is

A black body in a furnace at uniform temperature emits radiation. Which is true about directionality of emission?