Question 6:  If star A has a temperature of 4000 Kelvin and star B has a temperature of twice that, or 8000 Kelvin, how much more energy does it radiate per second than star A? From the Steffan-Boltzmann Law, we know that for the radiated energy, E goes as T to the 4th power, so 24 = 16 times Question 8:   The thickness of a plastic freezer storage bag is roughly 0.1 mm. How many wavelengths of red light is this?