MEASURING TEMPERATURE

There are several scales for measuring temperature. On the Centigrade scale the boiling point of water is fixed at 100° (one hundred degrees), its freezing point is at 0° (zero). The equivalent points on the Fahrenheit scale are at 212° and 32°.

When it is necessary to convert temperature readings from the Fahrenheit scale to the Centigrade, we subtract 32 and multiply by 5/9.

Sometimes scientists use the Absolute scale (Kelvin) in which the temperature is measured in degrees Centigrade from the point at which molecular motion ceases. Absolute zero is -273.1° С

The instruments measuring temperature, the thermometers, are nearly identical but each has a different scale. Most thermometers use mercury as an agent and we call them mercury thermometers. But at temperatures below - 39° С mercury freezes and becomes a solid. And so for measuring very high and very low temperatures we usually use electrical thermometers.

Task 1. Choose the right answer according to the text.

1. What temperature scale do we usually use in Russia?

a) Fahrenheit; b) Kelvin; c) Centigrade

2. What is the boiling point of water on the Fahrenheit scale?

a) 100°; b) 212°; c) 373°

3. When do we use mercury thermometers?

a) to measure very high temperatures;

b) to measure very low tempera­tures;

c) to measure average temperatures

Task 2. Find the appropriate Russian word combinations.

a) 1. boiling point; 2. to measure low temperature; 3. temperature
readings; 4. molecular motion; 5. freezing point; 6. to measure high
temperature

b) 1. молекулярное движение, 2. точка замерзания 3. изме­
рять высокую температуру, 4. показания температуры, 5. измерять
низкую температуру, 6. точка кипения.