S5 Physics B-Test 1st Semester

Equations of Motion:

• v = u + at I v = u - gt I v (t) = v (0) + at

• s = ut + ½ x at² I h = ut - ½ x gt² I s (t) = s (0) + v (0) x t + ½ x at²

• v² - u² = 2as I v² - u² = 2gh

Radioactivity:

Nucleus of an atom of an element that spontaneously disintegrates to emit alpha, beta, or gamma rays.

Natural Radioactivity:

- Phenomenon of spontaneous emission of radiation from certain elements on their own.
- Atomic number > 83

Artificial Radioactivity:

• Induced Radioactivity

• Phenomenon by which elements with atomic number <83 are made radioactive, by artificial or induced methods.

Ionizing Radiation:

- Any type of particle or electromagnetic wave that carries energy to ionize or remove electrons from an atom.

- Hazardous to health

Ionization:

Addition or removal of an electron to create an ion.

Curie:

- Traditional unit of radioactivity

- 3.7 x 10 10 disintegrations per second

Becquerel:

- S.I. Unit for Radioactivity

- 1 Bq = 1 disintegration per second

Mass Defect:

Delta m = Mass of nucleons - Mass of nucleus