# Blackbody curves

### Planck’s law of blackbody radiation

According to Planck's law of blackbody radiation, spectral energy density of radiation emitted from a blackbody in $$W \over m^3$$ as a function of wavelength $$\lambda$$ at a temperature $$T$$ in Kelvin is given by the equation: $$R = {{2 h c^2} \over \lambda^5}{1\over {e^{{hc}\diagup{k_B \lambda T}}}-1}$$ Where $$h$$ is Planck's constant $$6.63 \times 10^-23$$ $${Joule*second}$$, $$c$$ is the speed of light $${3 \times 10^8} {meter \over second}$$, and $$k_B$$ is Boltzmann's constant $$1.39 \times 10^{-23} {Joule \over Kelvin}$$

### Peak wavelength from Wien’s displacement law

Wien's displacement law allows for calculating the peak of the radiation curve which shifts with the temperature as described in Planck's law of blackbody radiation. The peak wavelength $$\lambda_{peak}$$ of the blackbody emission curve can be calculated by the following equation. $$\lambda{peak} = {{hc} \over x}{1 \over {k_B \lambda T}}$$ In this equation $$x$$ is a constant parameter equal to $$4.965114231744276$$.

Note: Blackbody radiation relies on an idealized concept. In application, radiation curves may experience wavelength dependence based on material characteristics.

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Kelvin
$$K$$
Celsius
$$^\circ C$$
Fahrenheit
$$^\circ F$$
$$\lambda_{peak}$$
$$um$$

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