Microwave Lab

The purpose of this experiment was to place marshmallows in a microwave and let it ride for 30 seconds and measure the frequency of the microwave, how many photons per second are oscillating in the microwave, and how much pressure do the photons exert on the side of the microwave.

Before continuing, it should be noted that a styrofoam cup of 100 grams of water was also placed in the microwave for 30 seconds as a part of experiment--needed to find total energy in the microwave. 

Note that the dimensions of the microwave--length, with, and height--are 35, 35, and 23 cm respectively.

After the marshmallows were microwaved for 30 seconds, the wavelength was measured for this standing wave 12 +/- 1 cm. Therefore one can calculate the frequency of this microwave using f=c/wavelength.

f= 2.5(10^9) hz
Next, energy per photon E-p = hf, where h= 6.636(10^-34) = E-p =1.66(10^-24) J
E = mc(Tf-Ti) = 100(4.186)(34)   (during the 30 sec, the temp elevated from 23C to 57C) 
E = 14232.4 J 
Therefore the number of photons n is equal to total energy divided by energy per photon n = E/E-p.
n = 8.57(10^27)
Moreover dividing photons by time n/t, one gets the number of photons oscillating per second in the microwave.  Photons per second = 2.88(10^26) n/s

Pressure, Pr, = E/(A*C*t) where A is equal to the are of the microwave wall. Plugging in the numbers yields Pressure total = 3.87(10^-7)  pascals
Furthermore pressure per photon Pr-p = Pr/n = 3.87(10^-7)/(8.57(10^27)) = 4.52(10^-35) pascals.