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Its on pg 974 of 2008 review notes.
given 4He, the atomic mass of the proton = 1.00728 amu
neutron = 1.00867 amu
atomic mass of 4He = 4.00260.
To find the mass defect we do
(mass of protons + mass of neutrons) - (atomic mass of 4He) = 0.02930.
Then the example asks to find the binding energy of the nucleus. This should be easy because we know that E = mc^2 where m-mass defect and c is the speed of light.
HOWEVER, in the example problem they say vertabem "0.02930 amu is the mass defect for 4He [ok we know this], and is interpreted as the conversion of mass into the binding energy of the nuclues. The rest energy of 1amu is 932 MeV, so using E = mc^2 we find that c^2 = 932 MeV/amu. [WTF? Where did that come from...seems so random]Therefore the binding energy is.."
B.E = (0.02930)(932) = 72.3 MeV
Essentially my question is why are they using 932MeV for c^2 rather than (3x10^-8)^2.
Thanks!!!!!
given 4He, the atomic mass of the proton = 1.00728 amu
neutron = 1.00867 amu
atomic mass of 4He = 4.00260.
To find the mass defect we do
(mass of protons + mass of neutrons) - (atomic mass of 4He) = 0.02930.
Then the example asks to find the binding energy of the nucleus. This should be easy because we know that E = mc^2 where m-mass defect and c is the speed of light.
HOWEVER, in the example problem they say vertabem "0.02930 amu is the mass defect for 4He [ok we know this], and is interpreted as the conversion of mass into the binding energy of the nuclues. The rest energy of 1amu is 932 MeV, so using E = mc^2 we find that c^2 = 932 MeV/amu. [WTF? Where did that come from...seems so random]Therefore the binding energy is.."
B.E = (0.02930)(932) = 72.3 MeV
Essentially my question is why are they using 932MeV for c^2 rather than (3x10^-8)^2.
Thanks!!!!!
