7/25/2019 Mercury in Glass Thermometer
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Mercury in glass thermometer
1. A mercury in glass thermometer works on the expansion and
contraction
of mercury in the bulb of the thermometer.
2. When the thermometer is used to measure the temperature of a
hot
object, the mercury in the bulb expands and forces the mercury
in the glass
tube to go up.
3. When the thermometer is used to measure the temperature of a
cold
object, the mercury in the bulb contracts and the mercury in the
glass tube
goes down.
Bimetallic Strip in Fire Alarm
1. A bimetallic strip is made of two dierent metal strip, such
us copper and
iron.
2. !opper expands faster than iron when heated.
3. "he forces that arise due to en e#ual expansion of the two
metals cause
the bimetallic strip to bend.
$. %imetallic strips are used as automatic switches in &re
alarms and as
thermostats in electrical appliances such as iron,
air'conditioners, ricecookers and refrigerators to keep the
temperature in these appliances
constant.
