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Question
The steam point and the ice point of a mercury thermometer are marked as 80° and 20°. What will be the temperature on a centigrade mercury scale when this thermometer reads 32°?
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Solution
Given:
Ice point of a mercury thermometer, T0 = 20° C
Steam point of a mercury thermometer, T100 = 80° C
Temperature on thermometer that is to be calculated in centigrade scale, T1 = 32° C
Temperature on a centigrade mercury scale, T, is given as:
T = `(T_1-T_0)/(T_100-T_0) × 100`
`=> T =(32-20)/(80-20) × 100`
`=> T=12/60 × 100`
`=> T = 120/6`
⇒ T = 20°C
Therefore, the temperature on a centigrade mercury scale will be 20o C.
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