Foundations of physics

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Created by
Jack H

Cards (12)

  • The 6 SI base units are:
    • length - metre
    • mass - kilogram
    • time - second
    • current - ampere
    • temperature - kelvin
    • amount of substance - mole
  • Prefixes change the order of magnitude of a quantity. Some examples of prefixes are:
    • P - 101510^{15}
    • T -101210^{12}
    • G -10910^{9}
    • M -10610^{6}
    • K - 10310^{3}
    • d - 10−110^{-1}
    • c - 10−210^{-2}
    • m -10−310^{-3}
    • μ\mu - 10−610^{-6}
    • n - 10−910^{-9}
    • p - 10−1210^{-12}
    • f - 10−1510^{-15}
  • Units for a quantity can be derived using equations and other units.
  • A scalar quantity has magnitude only, while a vector quantity has both direction and magnitude.
  • Quantities can only be summed when they have the same units, but they can be multiplied when they have different units.
  • A vector is represented with an arrow.
  • If two vectors are parallel, the resultant vector is their sum.
  • When two vectors act on the same plane but in opposite directions, the resultant vector is their sum, provided a negative direction is defined.
  • The resultant vector from two perpendicular vectors can be found using Pythagoras’ theorem and trigonometry. Draw the vectors in a triangle, with one vector leading to the next.
  • A vector can be resolved into its horizontal and vertical components using trigonometry.
  • When adding non-perpendicular vectors, you can use a scale diagram or trigonometric rules.
  • To subtract one vector from another, reverse the direction of the vector and add the vectors together.