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

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?

Which phenomenon explains why hot metal glows red then white as it is heated?

Radiation pressure (qualitative) arises because photons carry momentum. For a perfectly absorbing black surface perpendicular to a beam of light, the pressure is

Which device gives the closest laboratory approximation to a perfect black body for emission and absorption tests?

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?

The Stefan–Boltzmann concept (qualitative) states that for black bodies, the total radiated power per unit area is proportional to the fourth power of absolute temperature. Which consequence follows?

The spectral peak wavelength of a perfect black body shifts when its temperature changes. If the temperature increases, the peak wavelength

When designing thermal insulation, reducing radiative heat transfer is achieved by using low-emissivity layers. A practical example is

A grey body has emissivity less than 1 but independent of wavelength. Compared with a perfect black body at the same temperature, a grey body