Fundamental concepts in study of Earth and Solar System
The system comprises
- matter = made up of small particles held together by energy
- energy = the ability to do work -
- work = force x displacement (or distance)
Units = Joules = Newton* meter (N* m) = = kg* m2/ (s2)
More on energy
- force (F) = mass (M) x acceleration (A)
Units = Newtons (N) = (mass x length)/(time x time) = kg* m / (s2)
- acceleration = rate of change of velocity.
Units = meters/second per second = m/s2
Fundamental forces = strong, weak, gravitational, electromagnetic
The strong force holds nuclear particles and nuclei of atoms together
The weak force influences the interactions between nuclear particles and electrons
electromagnetic forces - interactions between charged particles
gravitational force - interactions between masses
power
= energy per second
Units = Watts (W) = Joules/second = J/s
Types of energy:
- Mechanical:
kinetic or energy of motion
potential
- chemical
- electromagnetic (waves/particles)
- heat or thermal
- nuclear
Can convert one form of energy to another and can convert matter to energy and energy to matter.
Matter
- Particles = fundamental (quarks), nuclear (protons, neutrons), sub-atomic (nuclei, electrons), atomic (atoms)
- quarks - positive and negative
- neutrons - neutral
- protons - positive
- electrons - negative
- atoms - neutral
- elements =elements are a classification scheme for atoms
elements differ from each other by the number of protons (and thus also electrons)
isotopes = elements that have different number of neutrons but the same number of protons
ions = elements that have fewer or more electrons than there are protons
ions have an electric charge
Elements are produced in stars - by a series of reactions between
Hydrogen (H) nuclei (protons), Helium (He) nuclei (alpha particles) and electrons
- these reactions produce all elements up to iron (Fe)
- heavier elements are formed by neutron capture to form stable heavy elements (up to lead (Pb) and bismuth (Bi)
- even heavier elements require rapid neutron absorption - this happens in the region of explosions outside neutron stars or black holes. These are unstable - radioactive.
Radioactive elements are elements with unstable nuclei. These decay
(decompose) by emitting nuclear particles and energy. Reach new stable
energy level. Decay produces alpha, beta and gamma particles.
Back to Geo lecture notes
Back to Geo 101 homepage