Measurements

Measurements

1. Analogue and Digital Meters

   • Analogue meters
     • Displays readings by deflection of a pointer over continuous scale
     • Readings are estimated when pointer lies between divisions of scale
   • Digital meters
     • Display readings as digits which change one at a time
     • No interpretation needed because values are in display
     • Advantages
       • Errors of parallax and shadowing are eliminated
       • Not sensitive to movement, analogue meters are

2. Measuring Distance

   • measured using a ruler
   • measurements can be made to an accuracy of 1mm (0.5mm at each end)
   • it's best to measure from the 1cm mark, remembering to subtract 1 cm from final reading

3. Measuring the Thickness of a Page of a Book

   • 1. Measure the thickness of the book (excluding the cover) with a ruler
   • 2. Count the total no. of sheets. Each sheets has 2 pages, so divide the total no. of pages by 2
   • 3. Count the no. of unnumbered sheets at the front and back of the book. Add this no. to the total no. of numbered sheets
   • 4. Divide thickness of book by total no. of sheets to calculate thickness of 1 page