origin of the universe

• 2 ferson who invented the big bang theory.

  alexander friedman and george lamaitre
• The explosion sent space, time, matter and energy in all directions.

  • This event is called “big bang”
• All the matter and energy in the universe are crammed into a tiny compact point sometimes called


  singularity
• short ranged (10-13 cm) attractive force which binds the nucleus.


  strong force
• long range force that binds atoms which can either be attractive or repulsive

  electromagnetic force
• short ranged force present in radioactive decay.

  weak force
• weak, long ranged, and attractive force which binds the Solar system.

  gravitational force
• theory that proposed that the planets were formed by the collision of the sun with a giant comet

  buffon's collision theory
• who proposed the tidal theory?

  jeans-jeffreys tidal theory
• refer to the gravitational forces exerted by one celestial body on another, especially in cases where one body is significantly more massive than the other.

  tidal forces
• According to the theory, planets was formed from materials pulled out in the sun.

  jeans-jeffrey's tidal theory
• proposed  the nebular theory?

  kant-laplace theory
• the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.

  nuclear fusion
• The first star are formed from contraction of gases and nuclear fusion.
• The Earth is approximately an oblate spheroid, meaning it is mostly spherical but slightly flattened at the poles and bulging at the equator.