Temperature (kelvin) is defined by agreed fixed points. These points are defined by the state changes of nearly pure materials, generally as they move from liquid to solid. Between these fixed points, Standard Platinum Resistance Thermometers (SPRTs) are used to interpolate temperature values. This mosaic of approaches produces measurement uncertainty which is not uniform over the entire range of temperature measurement. Temperature measurement is coordinated by the International Practical Temperature Scale, maintained by the BIPM.

Ex. 2. Answer the following questions

1. What was learned later about the Earth’s surface ?

2. How many unites of measure are internationally recognized currently ?

3. What is Standard Platinum Thermometer used for ?

4. What do special candela standard bulbs recreate ?

5. What are any measurements based on?

Ex. 3. Are these sentences true or false ?

1. Non-commercial measurement details were studied by scientists.

2. The candela standard is easy to recreate.

3. Voltage and resistance units are independent on current units.

4. Temperature (kelvin) is defined by non-defined fixed points.

5. Standard Platinum Resistance Thermometers (SPRTs) ar e used to interpolate voltage values.

6. Watt is derived from meter.

7. Ten independent units of measure are internationally recognized, currently.

Ex. 4. Fill the blanks using the following word words:

surface, poles, to define, reason, to attempt, length, to reproduce, metrology object.

Standard is an … oridea that can be used some accepted … Ideal standards can be … without uncertainty. The first ideal standard was … to create in the 19^>th century. It was connected with «meter» … standard. In the 19th century meter was … as one ten-millionth of the distance from the equator to one of the Earth’s … It was considered as the first ideal standard. Later it was learned that the Earth’s … an unreliable basis for a standard because the Earth could change its shape. Today there are carried out many calibration investigations w hich are widely used in … for establishing standards.

Ex. 5. Match the beginning with the endings based on the text

Ex. 6. Put the questions to the bold-typed words:

1. These bulbs recreate candela.

2. Luminance (candela) can only be reproduced to 5 %.

3. This organization coordinates temperature measurements.

4. Current is applied during the recreation of candela.

5. This mosaic of approaches produces measurement uncertainty.

Ex. 7. Make the summary of the text: «The modern standards of some physical quantities» using the following plan:

The definition of ideal standard.

The definition of Candela standard and Kelvin standard.

requirement – требование – талап; бап; міндетті ереже

technical standards – нормативно-технические документы – дәстүрлі техникалық құжаттар

technical system – техническая система – техникалық жүйе

formal document – официальный документ – ресми құжат

criterion – критерий (pl. criteria) – критерий, белгі

practice – методика – әдіс, әдіс – тәсіл жиынтығы