Presentation on theme: "Things You should Know Gravity Light Thermodynamics Atoms Particles."— Presentation transcript:
Things You should Know Gravity Light Thermodynamics Atoms Particles
Gravity With Relativity Gravity is not action at a distance, but objects responding to the curvature of Space and Time in their immediate neighborhood Kepler’s Laws are valid for almost all gravitationally bound systems. The centre around which things orbit is the centre of mass of the system.
Atoms Electrons orbit nucleus ( Protons and Neutrons) Held together by attraction of opposite electrical charge Possible energies described by spectrum Electrons can change energies by either absorbing or emitting light
Light Wave-Particle Duality Frequency, Energy and Wavelength are all related Different types of light described by electromagnetic spectrum Stars have an absorption spectrum : Light from hot surface (continuous) Minus light absorbed by gas in atmospheres (the star’s and Earth’s)
Thermodynamics Heat is a form of energy manifested in random (thermal) motion of molecules Temperature determines the average heat energy per molecule Pressure is force per unit area which equals the average thermal energy per unit volume Density is the average number of molecules per unit volume Hot opaque objects emit light in a continuous spectrum called a Planck curve which depends only on temperature At low temperature matter clumps together, as you add heat it flies apart
Heat Transfer Conduction – Heat energy passed from molecule to molecule via contact (mostly in solids) Convection – Heated material rises, taking its heat with it (requires gravity and large temperature difference) Radiation – Heat transferred by emission and absorption of light
Particle Physics Four Forces (interactions): Gravity, Electromagnetism, Weak, Strong Gravity – Stars, Solar System, Galaxy, Universe E&M – Atoms, Molecules, Bricks Weak – can transform one type of fermion into another Strong – Protons, Neutrons, Nucleus Each force carried by a gauge boson, matter particles are called fermions (Quarks and Leptons) each fermion has rules for how it interacts with the Gauge Bosons