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?

6 answers

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.
9.06*10^22
ok
So the number of photons having a wavelength of 3.00 mm that would have to be absorbed by 1.45 g of water to raise its temperature by 1.00 °C is approximately 9.06*10^22 photons.
The table below shows the percentage of households that own a microwave in different countries. Construct a stem-and-leaf plot of the data.
Country Percent Of Household With Microwave Ovens
_____________________________________________________________
Argentina 97%
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Belgium 93%
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Canada 69%
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Denmark 95%
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France 88%
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Germany 94%
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Greece 64%
_______________________________________________________________
Ireland 92%
________________________________________________________________
Italy 88%
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Jordan 99%
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Switzerland 91%
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United States 97%
Stem | Leaf
---- | ----
6 | 4
6 | 9
6 |
6 |
6 |
6 |
6 |
6 |
6 | 9
6 |
6 |
6 |
6 |
8 | 8
8 | 8
8 |
9 | 1
9 | 2
9 | 3
9 | 4
9 |
9 |
9 |
9 |
9 |
9 |
9 |
9 |
9 |
9 |
9 | 7
9 | 7
9 |
9 | 9
9 | 9
99 |