Calculate the energy release of an atom

In summary, the conversation discusses the handling of neutrinos and photons in a calculation involving energy release. The solution simplifies the equation by neglecting the mass of neutrinos and considering the annihilation of positrons and electrons in the energy release.
  • #1
Markus Kahn
112
14
Homework Statement
In the Sun and in other stars energy is generated by nuclear fusion. Consider only the
proton-proton cycle
$$4p\longrightarrow ^4\text{He}+2e^++2\nu_e + \gamma's$$
Calculate the energy released per ##^4##He nucleus.
Relevant Equations
Binding energy is given by ##E_B= (ZM_p +(A-Z)M_N-M_{Nucl})c^2##
First of, I have no idea what I'm supposed to do with the neutrinos and the photons. Can somebody explain how to handle these? The rest of what I tried is quite straight forward
$$\begin{align*}\Delta E &= 4M_p - M_{He} - 2 M_e + E_{\text{Neutrino and Photons}}\\&= 4M_p - (2[M_p+M_n]-E_B) - 2 M_e + E_{\text{Neutrino and Photons}}\\ &= 2(M_p-M_n)+ E_B-2M_e + E_{\text{Neutrino and Photons}},\end{align*}$$
where ##E_B## is the binding energy. The solution say we have
$$\Delta E=2\left(M_{p}-M_{n}\right)+E_{B}+2 M_{e},$$
and I have zero idea how they come to this expression.

Can somebody maybe help me here?
 
Last edited:
Physics news on Phys.org
  • #2
The positrons annihilate with electrons afterwards, it looks like they included this in the energy release.

Photons do not have mass and the mass of neutrinos can be neglected. They will carry away some of the released energy but you don't have to care about how exactly.
 

Related to Calculate the energy release of an atom

1. How do you calculate the energy release of an atom?

The energy release of an atom can be calculated using the famous equation E = mc², where E stands for energy, m for mass, and c for the speed of light. This equation was developed by Albert Einstein and is known as the mass-energy equivalence equation.

2. What factors affect the energy release of an atom?

The energy release of an atom can be affected by several factors, including the type of atom, the mass of the atom, and the amount of energy required to break the bonds within the atom's nucleus. Additionally, the energy release can also be affected by external factors such as temperature and pressure.

3. How is the energy release of an atom measured?

The energy release of an atom is typically measured in units of electron volts (eV) or joules (J). One electron volt is equivalent to the amount of energy gained by an electron when it is accelerated through a potential difference of 1 volt. One joule is equivalent to the amount of energy required to perform 1 watt of work for 1 second.

4. What is the significance of calculating the energy release of an atom?

Calculating the energy release of an atom is important in understanding the behavior and properties of atoms. It can also help in predicting the amount of energy that can be harnessed from nuclear reactions and in developing new technologies, such as nuclear power plants.

5. Can the energy release of an atom be negative?

No, the energy release of an atom cannot be negative. According to the mass-energy equivalence equation, energy release can only be positive or zero. A negative energy release would imply that the mass of the atom has decreased, which is not possible according to the laws of conservation of mass and energy.

Similar threads

Replies
1
Views
969
  • Advanced Physics Homework Help
Replies
1
Views
2K
  • Advanced Physics Homework Help
Replies
2
Views
1K
  • High Energy, Nuclear, Particle Physics
Replies
14
Views
1K
  • Advanced Physics Homework Help
Replies
2
Views
2K
  • Astronomy and Astrophysics
Replies
2
Views
1K
  • Advanced Physics Homework Help
Replies
1
Views
998
  • Advanced Physics Homework Help
Replies
4
Views
4K
  • High Energy, Nuclear, Particle Physics
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
10
Views
4K
Back
Top