Page 53 - Physics

Measurement

The curve in the upper surface of the liquid is called the Task 2.7
meniscus. The meniscus can curve upward (concave)
or downward (convex) depending on the liquid and Fill some water in a drinking
the material of the cylinder. The volume of the liquid cup then pour the water
into a graduated measuring
is read at the top of the meniscus or at the bottom of cylinder. Measure and
the meniscus, as illustrated in Figure 2.28 (a) and (b), recorded the volume of
respectively. Note that the eye level should be in line water. What is the reading
with the meniscus of the liquid. on the cylinder?

Measurement of volume
using a burette
A burette is a vertical
cylindrical piece of laboratory
glassware with a volumetric
graduation on its full length
Mercury Water and a precision tap, or
stopcock on the bottom,
shown in Figure 2.30. It is
used to dispense a required
amount of a liquid reagent
(a) (b) for which high precision is
desired. A burette is graduated
Figure 2.28: Reading the volume of liquids in a from the top downwards and
measuring cylinder measures the volume of a
liquid that runs out from it.
For example, Figure 2.29, shows a 1 000 ml measuring
cylinder containing blue-coloured water. The volume
of water is 700 ml equivalent to 700 cm .
3

Figure 2.29: A 1 000 ml graduated cylinder Figure 2.30: A burette

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Physics Form 1 Final.indd 47 16/10/2024 20:55