-ii-Length
Measuring Length.
Length is “the distance between two points in a space”.
According to SI units, the length quantity is expressed in meter.
There are several kinds of measuring devices used to measure quantity of length, among others, are as follows.
Tools used…
a- Measuring tape.
b- Rule.
c- Vernier callipers.
d- Micrometre
Revise your Hany El-Gezawy notes
a- Measuring tape
how to use it
b- Rule
The most common, and the best known, piece of measuring equipment
What is Zero error?
Reducing reading errors
1- Taking several readings of the subject to be measured can also help to reduce reading errors
2- Avoid parallax error.
Parallax error
Always align your eye with the position being measuredWhen using such instruments, parallax error must be avoided.
d- Micrometre
The measurement of a small distance (use of a micrometre screw gauge)
Micrometres are used to measure small distances accurately (has accuracy until 0.01 mm. The screw micrometre is usually used to measure tiny or small objects.)
Reading micrometer
http://www.planetspring.com/pages/how-to-measurement-micrometer.php
MORE about
c- Reading vernier callipers
http://www.tresnainstrument.com/how_to_read_a_vernier_caliper.html
Hany El-Gezawy
IGCSE Physics 