Measurement | Physics for GCSE/IGCSE - Year 11 PDF Download

Measuring Length & Volume

• Rulers can measure small distances accurately, typically to the nearest millimeter (mm).
  • A ruler can precisely measure small distances to the nearest millimeter.
    
• When measuring larger distances (a few meters), a tape measure is suitable, while for even larger distances, a trundle wheel is more appropriate.
  
• Measuring Cylinders
  • Volume Measurement: Measuring cylinders are utilized to measure the volume of liquids accurately.
  • Calculating Irregular Shapes: By noting the change in volume, a measuring cylinder can determine the volume of irregular shapes.
    

Measuring Time

• Stop-clocks and stopwatches serve the purpose of gauging time spans.
• Human reaction time is a crucial consideration in timing intervals.
• The duration of human reaction time can notably affect measurements, particularly in instances where the time spans being measured are extremely brief, such as those shorter than a second.

Multiple Readings

• When measuring the thickness of a single sheet of paper, obtaining precise results is challenging due to its minuscule size.
• However, by measuring the thickness of 100 sheets of paper, accuracy improves significantly.
• Dividing the total thickness by 100 yields an accurate measurement for the thickness of one sheet.
• This method, which involves collecting data from numerous measurements and then dividing by the quantity, is effective for obtaining precise values for small measurements.
• Similarly, in determining the time period of a pendulum, one can measure the time for 10 swings and then calculate the average by dividing by 10.