Universe Models, Solar System Structure, and Star Formation
Geocentric and Heliocentric Universe Models
Geocentric Model (Aristotle)
The Earth is considered the center of the universe, fixed and immobile. A celestial sphere encompasses the sky, the Sun, Moon, planets, and fixed stars. Aristotle’s universe was divided into two parts: the celestial world and the terrestrial world. The celestial realm was perfect, and its only movement was thought to be circular. Tycho Brahe later rejected the existence of crystalline spheres carrying the planets after observing
Read MoreNewton’s Laws of Motion: Understanding Force and Acceleration
Newton’s Second Law
Newton’s Second Law states that when a force is applied to an object (a “body”), it accelerates in the direction of the force. The acceleration is directly proportional to the magnitude of the force and inversely proportional to the mass of the object:
a = F / m or F = ma
The Second Law provides an explicit formula and is therefore one of the most useful. However, it can also be one of the most confusing for physics students. The problem arises when expressed as follows:
A formula
Read MoreThermodynamics: Principles and Applications
Thermodynamics
Introduction: Thermodynamics is a branch of physics that studies the relationships between heat and work. Systems can be classified as open when mass exchange occurs, or closed when the average mass remains constant.
Extensive properties are mass-dependent, while intensive properties are not. Important concepts include thermodynamic variables (pressure, volume, and temperature), which define the thermodynamic state of a system, and functions of state (enthalpy, internal energy, etc.
Read MoreKey Figures and Films of Italian Neorealism
Robert Rossellini
- Neorealism trilogy: Germany Year Zero, Paisa, Rome Open City
- “There are many kinds of neorealism. Everyone has his own. Mine was a moral position, an effort to understand myself inside a phenomenon.”
Rome Open City (1945)
Right when WW2 ended.
- Engineer Giorgio, priest Don Pietro, Pina and Francesco, Son Marcello, Giorgio’s ex-Girlfriend Marina (betrayed resistance in exchange for drugs and fur coats)
- Scene when Pina got shot: “Few scenes in cinema have the force of that in which Magnani,
Space Exploration: History and Fundamentals
C = 2πr v = √(GM/r) {G-m3kg-1s-2} a = v2/r {r=Er+orbr} n1l=tendencyStaySameSpeedunlessForce n2lF=ma n3l=f-f f12=Gm1m2/r122 w=fd v=√(2gh) ep=-GerthMobj/r v=√(Gm(2/r-1/a)) p>=mv> f>t2-1=p2-1> mf linear mr_ mf expo..v2-1 _v2-1 is/ exh v{ion engines}
Planetary Exploration Stages
What stage of planetary exploration follows sending a successful flyby? Orbiter
Historical Parallels and Mythology
What historical era does our golden planetary age resemble? Age of Maritime Greek Mythology
Which
Read MoreUnderstanding Energy: Kinetic, Potential, and Transformations
Understanding Energy
1. How do you define energy? It is the ability to produce work.
Main Forms of Energy
2. Main forms of energy: heat, light, electrical, chemical, atomic, mechanics.
Mechanical Energy
3. What is mechanical energy? It is a form of energy that corresponds to work produced by a force of mechanical origin.
4. There are two kinds of mechanical energy: kinetic and potential.
Kinetic Energy
5. A body in motion has kinetic energy.
6. The value of the kinetic energy of a body is equal to half the
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