General Physics (PHY 2140). Lecture 20. Modern Physics Nuclear Energy and Elementary Particles Fission, Fusion and Reactors Elementary Particles Fundamental Forces Classification of Particles Conservation Laws. Chapter 30. Chapter 30.
Review Problem: A beam of particles passes undeflected through crossed electric and magnetic fields. When the electric field is switched off, the beam splits up in several beams. This splitting is due to the particles in the beam having different
D. some combination of the above
E. none of the above
v = E/B
In the first atomic bomb, the energy released was equivalent to about 30 kilotons of TNT, where a ton of TNT releases an energy of 4.0 × 109 J. The amount of mass converted into energy in this event is nearest to: (a) 1 g, (b) 1 mg, (c) 1 g, (d) 1 kg, (e) 20 kilotons
(c). The total energy released was E = (30 ×103 ton)(4.0 × 109 J/ton) = 1.2 × 1014 J. The mass equivalent of this quantity of energy is:
Note: 1 gram TNT = 4184 J (exactly)
SCRAM = Safety Control Rod Axe Man
2% of sun’s energyis carried by neutrinos
Disadvantages of fusion power
Deuterium- tritium reactor
Deuterium- deuterium reactor
So need 108 K for 1 second
To be constructed in Cadarache in the South of France.
The scattering of two electrons via a coulomb force
This virtual photon is said to mediate the electromagnetic force. The virtual photon can never be detected because it only lasts for a vanishing small time.
An simple example of a Feynman diagram
8.3x10-17 s for p0