Английский язык. Ильичева Н.А - 39 стр.

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   where α, the proportionality constant, is called the coefficient of linear f)
   ……… for the particular material and has units of (C°)-1.
       We find that for steel α = 12 ⋅ 10-6 (C°)-1. The increase in length when it is
   at 40° will be ∆L = (12 ⋅ 10-6/C°) g) (………) (40° – 20°) = 4.8 ⋅ 102 m, or h)
   ……… cm.
       When the temperature decreases to - 30° C, ∆T = - 50° C. So the chnage
   in length is ∆L = (12 ⋅ 10-6/C°) (200 m) i) (………) = - 12.0 ⋅ 10-2 m or a
   decrease in length of j) ……… cm.

15. Opening a tight jar lid.
Your mother can’t open a tight jar lid. You offer her your help. Fill in the gaps
in the conversation with the words from the list:
                        expand, cope, jar, metal, tight, hot
Mother: I can’t open this a) ……… lid. It’s too b)……… .
You: Shall I help you, mum?
Mother: I don’t think you will c) ……… with it either. But you may try if you
wish.
You: Look, mum. I’m just holding it under d) ……… water for a short time.
Then a little effort and the lid is open.
Mother: I can’t understand why e) ……… water has made it easier to open.
You: Hot water has made the lid f) ……… .
Mother: But the jar was also struck by hot water, so it must have g) ………ed
too.
You: The lid is made of h) ……… and i) ………s generally j) ……… more than
glass for the same temperature.

16. Anomalous Behavior of Water Below 4° C.
A. State whether the following sentences are true or false.
a) Most substances expand with an increase in temperature.
b) Water at 0° C increases in volume until it reaches 4° C.
c) Water has its greatest density when it freezes.
d) Ice is less dense than water.
e) The water at the bottom of a lake is usually frozen first.
f) Water expands as it freezes to ice.

B. Choose the correct word. Then tell your classmates that the complete
   freezing of lakes and rivers could cause sever damage to their plant and
   animal life. Explain what processes prevent it.

   When the water in a lake or river is above 4° C and begins to cool by contact
   with cold air, the water at the a) surface / bottom sinks because of its b)
   smaller / greater density and it is replaced by warmer water from c) below /