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quickclick330
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Energy Problem--what did I do wrong?
Fusion (or "thermonuclear") reactions take place inside a star such as our Sun. One fusion reaction results from a collision between a proton (1H) and a deuteron (2H, the nucleus of "heavy" hydrogen, consisting of a proton and a neutron). When these two nuclei touch, they undergo a nuclear reaction, forming a helium-3 (3He) nucleus (containing two protons and one neutron) and a high energy photon, called a gamma ray.
1H + 2H 3He +
One "unified atomic mass unit", denoted by the symbol "u", is equal to 1.66 10-27 kg. The rest mass of the proton is 1.0073 u, the rest mass of the deuteron is 2.0136 u, the rest mass of the helium-3 nucleus is 3.0155 u, and the gamma ray is massless.
so...
rest masses
proton = 1.0073 u
deuteron = 2.0136 u
helium-3 nucleus = 3.0155 u
What is the kinetic energy of the helium nucleus plus the energy of the photon in the final state? Because you will be calculating a small difference of large quantities, you will need to use 5 or more significant figures in this calculation.
KHe + E = joules
*I've aready found out that the equation is:
mprotonc^2 + mdeuteronc^2 +Ui = mheliumc^2 +Khelium + Egamma
*Eand earlier in the problem I got that the Ui between the proton and the deuteron is 1.152e-13 J
so to find out mc^2 for the proton, deuteron, and helium,
(for the proton)
= (1.0073u) *(1.66e-27 kg) *(3e8)^2 = 1.5049062 J
(for deteron)
= 3.0083184 J
(for helium)
= 4.505158 J
so you would sove for Khelium + Egamma and get
Khelium + Egamma = mprotonC^2 +mdeutronC^2 +Ui - mheliumc^2
and i get 9.5876e-13...which is wrong?
Where have I gone wrong? Any help is greatly appreciated! thanks!
Fusion (or "thermonuclear") reactions take place inside a star such as our Sun. One fusion reaction results from a collision between a proton (1H) and a deuteron (2H, the nucleus of "heavy" hydrogen, consisting of a proton and a neutron). When these two nuclei touch, they undergo a nuclear reaction, forming a helium-3 (3He) nucleus (containing two protons and one neutron) and a high energy photon, called a gamma ray.
1H + 2H 3He +
One "unified atomic mass unit", denoted by the symbol "u", is equal to 1.66 10-27 kg. The rest mass of the proton is 1.0073 u, the rest mass of the deuteron is 2.0136 u, the rest mass of the helium-3 nucleus is 3.0155 u, and the gamma ray is massless.
so...
rest masses
proton = 1.0073 u
deuteron = 2.0136 u
helium-3 nucleus = 3.0155 u
What is the kinetic energy of the helium nucleus plus the energy of the photon in the final state? Because you will be calculating a small difference of large quantities, you will need to use 5 or more significant figures in this calculation.
KHe + E = joules
*I've aready found out that the equation is:
mprotonc^2 + mdeuteronc^2 +Ui = mheliumc^2 +Khelium + Egamma
*Eand earlier in the problem I got that the Ui between the proton and the deuteron is 1.152e-13 J
so to find out mc^2 for the proton, deuteron, and helium,
(for the proton)
= (1.0073u) *(1.66e-27 kg) *(3e8)^2 = 1.5049062 J
(for deteron)
= 3.0083184 J
(for helium)
= 4.505158 J
so you would sove for Khelium + Egamma and get
Khelium + Egamma = mprotonC^2 +mdeutronC^2 +Ui - mheliumc^2
and i get 9.5876e-13...which is wrong?
Where have I gone wrong? Any help is greatly appreciated! thanks!
