posted by Luke on .
Microwaves are used to heat food in microwave ovens. The microwave radiation is absorbed by moisture in the food. This heats the water, and as the water becomes hot, so does the food. How many photons having a wavelength of 3.00 mm would have to be absorbed by 1.45 g of water to raise its temperature by 1.00 °C?
E for 3.00 mm is
E = hc/wavelength. Convert wavelength in mm to m. That gives E for 1 photon which is q/photon
q needed to raise T H2O is
q = mass H2O x specific heat H2O x delta T = 1.45g x 4.184 x 1 = estimated 6 J
Then q/photon x # photons = estimated 6 and solve for # photons.