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Nuclear fusion is a nuclear reaction that two or more atomic nuclei collide at a high speed and join to form a new type of atomic nucleus. Matter is not conserved in this process because some of the mass of the fusing nuclei is converted to photons which are released though a cycle. Fusion is the process that powers our Sun and the stars.

The fusion of two nuclei with lower masses than iron generally releases energy, while the fusion of nuclei heavier than iron absorbed energy. This is oppositely true for nuclear fission. When heavier elements fuse in the atmosphere the process gives rise to nucleosynthesis, the creation of heavy elements during events such as supernovae.

In order for fusion to occur, a substantial energy barrier of electrostatic forces must be overcome. At far distances, two nuclei will repel each other because of the repulsive electrostatic force between their positively charged protons. If the two nuclei’s can overcome to electrostatic repulsion and be brought close together fusion can occur.

For the energy to be produced from a fusion reaction to be useful it must meet the following criteria.
- Be exothermic
- Involve low Z nuclei
- Have two reactants
- Have two or more products
- Conserve both protons and neutrons

Fission and Fusion

Compare and contrast the processes of fusion and fission. Describe the challenges in harnessing fusion technology for domestic energy needs

Proton Fusion

See the attached file. The sun is powered mostly by the fusion of two protons into the following particles: H^1+ H^1→ H^2+e+ ν Classically for this reaction to happen, the protons must come close enough to each other to "touch". Assume the proton is a uniformly charged, solid sphere of radius rp = 1.5 x 10-18m and tha

Physics: Heat of unknown substance

See attached file for graph. 6. The graph at right shows the temperature of 350 grams of an unknown substance as it is cooled from a gas to a solid by extracting a constant amount of energy per minute. Assume that all the changes on the graph occur at round numbers. a. Which phase of the substance has the highest specific

Physics Problems: Sample Questions

Consider a hot air-balloon. The deflated balloon, gondola, and 2 passengers have a combined mass of 315 kg. When inflated, the balloon contains 871m^3 of hot air. Find the temperature (degrees C) of the hot air required to lift the balloon off the ground. The air outside the balloon has a temperature of 20.2 degrees C and a pres

Scientific Method, Galileo & History

Hello. Please help me with the following: 1. What harm can be done by reporting false or poor data in a scientific report ? How does the scientific method correct such errors and fraud ? 2. What observations did Galileo make that reinforced the heliocentric model ? Why did these observations contradict the geocentric model ?

Heat and Thermodynamics: Change of state

Please help with the following problem. Provide at least 400 words. Describe the phenomenon of latent heat with respect to the process of heating a block of ice to eventually create steam.

Total of twenty questions related to work, energy, power, simple pendulum, electricity, electric power, gravitational potential energy, kinetic energy ,Celsius temperature, Kelvin temperature, specific heat, heat and Ideal gas law.

1. A force of 7.2 N acting on a 1.0-kg object initially at rest moves it through a parallel distance of 2.5 m. How much work is done on the object? 2. Neglecting friction, what is the speed of the object in Question 1 when it has moved 2.5 m? 3. A 0.10-kg ball is dropped from a height of 10 m and rebounds to a height

Heat Transfer and Insulated Thermos

Show ALL your work, including the equations used to solve the problems. An insulated Thermos contains 13cm^3 of hot coffee, at a temperature of 80.0ºC. You put in a 12.0-g ice cube at its melting point to cool the coffee. By how many degrees has your coffee cooled once the ice has melted? Treat the coffee as though it were p

Greco-Roman and Germanic fusion

After about 500 AD, Western Civilization became a "fusion" of the classical world (Greco-Roman civilization) and the Germanic peoples of northern and western Europe--how did this come about? a. What elements of Greco-Roman civilization survived to become part of the medieval world? b. How was European government, socia

Latent Heat: Melting of Ice

Calculate the latent heat of fusion from the heat balance equation. Compare this value with the value given in the textbook. 1. What would the temperature of the calorimeter mixture be if you added too much ice and not all of it melted? 2. What affect would there be on the calculated value of L if we read the final mixtu

Multiple choice questions on mechanics and heat & thermodynamics

Question 1 : At t=0, a wheel rotating about a fixed axis at a constant angular acceleration has an angular velocity of 2 rad/s. Two seconds later it has turned 5 complete revolutions. What is the angular acceleration of this wheel? multiple choice: a : 17 rad/s^2 b : 14 rad/s^2 c: 20 rad/s^2 d: 23 rad/s^2 Question 2 :