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The resistances of the platinum wire of a platinum resistance thermometer at the ice point and steam point are 8 and 10 respectively. After inserting in a hot bath of temperature 400 , the resistance of platinum wire is :
(2) 16
Platinum resistance thermometer: Rt=R0(1+ t), i.e. R varies linearly with t.
Rt-R0R100-R0= t100
Rt-810-8= 400100=4
Rt-8=8
Rt=16
Answer: (2)
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