# Efficiency and temperature of cooking device

1. Dec 9, 2008

### germblaster

1. The problem statement, all variables and given/known data

Suppose a cooking device has a power of P Watts. The temperature of the bulb which radiates heat is determined to be T (in Kelvin). Write an expression for efficiency in terms of T and P.

2. Relevant equations

E = $$\sigma$$$$T^{4}$$ Stefann Boltzmann equation
$$\eta$$= heat/electrical input

3. The attempt at a solution

Efficiency = $$\sigma$$$$T^{4}$$*A/P, where A is area.
Is the amount of heat simply given by the Stefann-Boltzmann equation?
Should I use the Planck distribution?
Is electrical input simply equatl to P?