Physics

Physics

1. Measurements and units

   • Numbers and units
     • Physical quantity- a complete measurement made up of a number and unit
     • G (giga)- 1,000,000,000
     • M (mega)- 1,000,000
     • k (kilo)- 1,000
     • d (deci)- 1/10
     • c (centi)- 1/100
     • m (milli)- 1/1,000
     • (micro)- 1/1,000,000
     • n (nano)- 1/1,000,000,000
   • SI units / Base units
     • (Le Systeme International d'Unites)
     • Mass - kilogram kg
     • Time - second s
     • Length - metre m
   • Measuring length and time
     • Length
       • Rule
       • Caliper
       • Micrometer
         • A revolving barrel with an extra scale on it
         • The most accurate method of measuring length
       • Vernier calipers
         • An extra sliding scale fitted to some length- measuring instruments
       • Tape
     • Time
       • Stopclock / stopwatch
       • Analogue & Digital
       • Automatic timing
         • e.g. a light sensor starts and stops the time when the pendulum crosses the light beam
   • Volume & Density
     • Density = mass / volume
       • kg / cm3
       • Density of water = 1 g / cm3
     • Volume - the quantity of space an object takes up - cubic metre (m3)
       • 1 litre = 1,000 cm3 = 1,000 ml
   • Measuring volume and density
     • Volume
       • Liquid
         • Measuring cylinder
       • Regular solid
         • Length*Width*Height
       • Irregular solid
         • Measuring the difference in volume of water when placing it into a water filled measuring cylinder
         • Using a displacement can / eureka can