Physical Quantities

Cards (13)

  • SI base units
    • mass- kilograms
    • length- meters
    • time- seconds
    • temperature- kelvin
    • current- ampere
    • amount of substance- mole
    • luminous intensity- candela
  • Scalar quantity has only a magnitude
  • Vector quantities have both magnitude and direction
  • Accuracy is how close the measured value is to the true value of the quantity being measured.
  • Precision is how close the measured values are to each other
  • Zero error is a type of systematic error which occurs when an instrument gives a reading when the reading is supposed to be zero
  • Random errors are unpredictable fluctuations in a reading as a result of uncontrollable factors such as human error, environmental conditions
  • Systematic errors arise from the use of faulty instruments or flaws in the experiment
  • Absolute uncertainty is where the uncertainty is given as a fixed quanitity
  • Percentage uncertainty is where the uncertainty is given as the percentage of the measurement
  • Relative uncertainty is where the uncertainty is given as a fraction of the measurement
  • Average value = (sum of all readings) / number of readings
  • Prefixes
    • pico- 10^-12
    • nano- 10^-9
    • micro- 10^-6
    • milli- 10^-3
    • centi- 10^-2
    • deci- 10^-1
    • kilo- 10^3
    • mega- 10^6
    • giga- 10^9
    • tera- 10^12