Monday, July 11, 2011

Science: Types of Forces

Types of Forces

There are four types of forces:
  1. Gravitational
  2. Electromagnetic
  3. Weak Nuclear
  4. Strong Nuclear

Science: Motion and Laws of Motion

Motion and Laws of Motion

Science: Motion
Motion is an act of changing position with respect to a reference point.
It can be measured by:
  • speed (scalar quantity) – m/s, km/hr, mi/s (magnitude) 
  • velocity (vector quantity) – m/s eastward (magnitude direction) 
  • acceleration – m/s2, km/hr2

Laws of Motion

Law of Inertia
  • The resistance to change in motion
Law of Acceleration
  • directly proportional with force and inversely proportional with mass; a=F/m
Law of Interaction
  • for every action, there is equal / opposite reaction
Law of Universal Gravitation
G=6.67 x 10-11

Science: Astronomers and their Contributions

Astronomers and their Contributions

Science: Astronomers and their Contributions
  • Ptolemy, Claudius – Geocentric model (earth-centered)
  • Copernicus, Nicholaus – Heliocentric model (uniform circular motion)
  • Tycho Brahe – astronomical instrument
  • Johannes Kepler – Law of Orbit, Law of Equal Areas, Law of Period
  • Galileo Galilei – telescope, thermometer, compass, pendulum, satellite of Jupiter
  • Isaac Newton – Law of Inertia, Law of Acceleration

Science: Measurement

Measurement and Seven Fundamental Quantities

Measurement is a process of comparing unknown quantity with a standard.

(7) Seven Fundamental Quantities
1. length – meter
2. mass – kilogram
3. time – seconds
4. temperature – Kelvin
5. amount of substance – mole
6. electric current – ampere
7. luminous – candela

Science: Scientific Method

The Scientific Method

The Scientific Method
  1. Identify the problem
  2. Observation
    • Senses (quality)
    • Measure (quantify)
  3. Gather data (table, chart, graph, diagram)
  4. Formulate the Hypothesis (wise guess)
  5. Experiment
    • Independent variable
    • Dependent variable
  6. Interpret
  7. Draw Conclusion
  8. Recommendation/Application