The increase
in the volume of water as its temperature is lowered from 40C
to 00C is known as anomalous expansion of
water or peculiar behavior of water.
Solid, liquid
and gases are expand on heating is called thermal expansion.
There are three
scales of temperature.
The expansion
inlength of metallic objects is called linear expansion.
The expansion
involume of metallic objects is called volumetric
expansion.
Liquids expand
on heating and contract on cooling like solid.
Gases also expand
on heating and contract on cooling.
The electric
fire alarm works on the principle of expansion.
An instrument
used for measuring temperature, is called a thermometer.
A common
thermometer in everyday use consists of a glass bulb (B)
connected to a thin glass tube called capillary tube (T) when
heated. The capillary tube is surrounded by thick glass tube is called stem
(S).
Celsius or
centigrade scale of temperature was introduced by a SwedishastronomerCelsius.
In the above
scale the ice point is marked as 00C and
boiling point is marked as 1000C.
Second scale of
temperature is Fahrenheit and introduced by ScientistFahrenheit.
The ice
point of this scale is 320F and boiling
point of is marked 2120F.
The third scale
of temperature is Kelvin and this scale was introduced by scientist
Lord Kelvin.
The ice
point of Kelvin is 273 K and boiling point
of water is marked 373 K.
The normal
human body temperature is about 36.90C or 98.40F.
Expansion and
contraction of solids and liquids can give rise to tremendous force.
Bimetallic
strips are used in electric iron and fire alarms.
Thermometers
have mercury or alcohol inside them. It works on
the principle of thermal expansion.
Which material will expand on
heating?
a) Solids
b) Liquids
c) Gases
d) All of these
