The Scientific Endeavour (Chapter 1)

• Physical Quantities 


  -Can be measured by a device or an instrument

  -Measurement consists of a numerical magnitude and a unit.

  -S.1. Units are used to standardise any measurements made
• Quantity is the amount of something that exists.
• S.1. Unit

  Length - meter (m)

  Time - second (s)

  Temperature - kelvin (K)

  Mass - Kilogram (Kg)

  Volume - Metre cube (M^3)

  Area - Metre square (M^2)

  Density - Kg/m^3
• Accuracy & Precision


  Accuracy: How close the data is to the true value

  Precision: How close the data is to one another
• Types of errors


  Zero error: When a instrument gives a non-zero reading when the measured quantity should be zero

  Parallax error: When the marking on an instrument is viewed from the wrong angle
• Volume


  Measuring cylinder, Beaker, Burette
• Mass

  Electronic balance
• Time

  Digital stopwatch
• Length

  Vernier calipers/ Rulers
• Temperature


  Thermometer
• Diameter


  Digital Calipers (tails)
• Qualitative


  Senses and descriptive
• Quantitative


  Senses and measurements and numerical
• Independent variable


  Changed variable
• Dependent variable


  Measured variable