The notation "20 degrees Celsius" on a measuring cylinder indicates the reference temperature at which the measurements are being taken or recorded.
Measuring cylinders are commonly used in laboratory settings to measure the volume of liquids. Since the volume of a liquid can be affected by temperature changes, it is important to standardize the measurements by specifying the temperature at which they are taken. The most common reference temperature used in scientific experiments is 20 degrees Celsius (°C).
By stating "20 degrees Celsius" on the measuring cylinder, it serves as a reminder to the experimenter that the volume readings displayed on the cylinder are accurate at that specific temperature. This allows for consistency and comparability of measurements between different experiments or across different laboratory procedures.