Zusammenfassung der Ressource
measurements
- measuring length
- metre ruler
- precision: 1mm/0.1cm
- avoid parallax errors
- eye level must be placed directly above the length measured
- vernier calipers
- accuracy: 0.01cm
- check for zero errors
- measures short lengths, 1cm - 10cm
- micrometer screw gauge
- meeasuring lengths up to 1cm
- accuracy: 0.1mm
- take note of zero error !
- basic physical quantities, s.i. units
- base quantities
- e.g. length, mass, time
- derived quantities
- e.g. area, volume, speed, density
- measurements of time
- s.i. units: seconds
- regular repeating motions: oscillations
- one whole oscillation: period
- period of a pendulum depends on length of pendulum
- if the length is increased, the period of the pendulum increases
- Why take the average of 20 oscillations
instead of the timing of 1?
- human reaction time is 0.3 - 0.4 sec late
- why is the angle of
displacement of the swing
small?
- to keep the oscillation in a single plane