Nuclear Physics Test. 2

An alpha particle consists of two protons (each with charge +e) and two neutrons (no charge), giving it a total charge of +2e.

Similar to fission, the fusion process converts a small amount of mass into a large amount of energy, so the resulting nucleus has less mass than the sum of the initial nuclei.

In a cloud chamber, charged particles leave trails of condensation in a supersaturated vapor, making their paths visible for study.

Solid-state detectors use a semiconductor diode (a p-n junction) where radiation creates electron-hole pairs, generating a detectable electrical pulse.

After one half-life, 1/2 remains. After a second half-life, half of the remaining sample decays, so (1/2) * (1/2) = 1/4 remains.

In negative beta decay, a neutron becomes a proton, and an electron and an antineutrino are emitted to conserve lepton number.

One hour contains 60 minutes, which is equal to three half-lives (60/20 = 3). The fraction remaining after 'n' half-lives is (1/2)ⁿ. So, after 3 half-lives, the fraction is (1/2)³ = 1/8.

Gamma decay is the release of energy from an excited nucleus. No protons or neutrons are lost, so both the atomic number (Z) and mass number (A) remain unchanged.

In Einstein's famous mass-energy equivalence equation, 'c' is the constant representing the speed of light in a vacuum (approximately 3 x 10⁸ m/s).

This reaction shows a heavy Uranium nucleus splitting into two smaller nuclei (Barium and Krypton) and releasing more neutrons, which is the definition of nuclear fission.

Friction is an emergent force resulting from electromagnetic interactions between surfaces. The four fundamental forces are Strong, Weak, Electromagnetic, and Gravitational.

Binding Energy (in MeV) is calculated by multiplying the mass defect (in amu) by 931.5. So, Energy = 0.04 amu × 931.5 MeV/amu = 37.26 MeV.

The half-life of Carbon-14 is about 5730 years, which makes it suitable for dating ancient organic materials.

Henri Becquerel discovered radioactivity in 1896 when he observed that uranium salts could expose a photographic plate without any light source.

The peak of the binding energy curve is around Iron-56, making it the most stable nucleus. Fission and fusion both release energy by moving towards this peak.

Gamma rays are a form of electromagnetic radiation (photons) with very high energy, no mass, and no charge.

The strong force is extremely powerful but only acts over very short distances, typically the diameter of a small nucleus (around 1 femtometer or 10⁻¹⁵ m).

The decay constant (λ), which represents the probability of decay per unit time, is inversely proportional to the half-life. The constant 0.693 is the natural logarithm of 2.

Control rods are made of materials that are strong neutron absorbers, like Cadmium or Boron, to regulate or shut down the fission chain reaction.

After detecting a particle, the G-M tube needs a brief recovery period to reset before it can accurately detect the next one. This period of insensitivity is the dead time.