Calculating Skin Temperature: Using a Thermometer with Resistance Equation

Libra_girl
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A thermometer is used to measure the skin temperature of a patient. This thermometer works by having a wire in contact with the skin. As the temperature of the skin changes it will change the temperture of the wire and hence the resistance of teh wire. If the wire has a resistance of 40 Ohms at 30 degrees, what will its resistace be at 36 degrees? (The temperature coefficent of resistivity of the wire is 5.0x10^-2 K^-1.

What equation should I use to solve this?
 
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Libra_girl said:
A thermometer is used to measure the skin temperature of a patient. This thermometer works by having a wire in contact with the skin. As the temperature of the skin changes it will change the temperture of the wire and hence the resistance of teh wire. If the wire has a resistance of 40 Ohms at 30 degrees, what will its resistace be at 36 degrees? (The temperature coefficent of resistivity of the wire is 5.0x10^-2 K^-1.

What equation should I use to solve this?

Check out the bottom of http://hyperphysics.phy-astr.gsu.edu/hbase/electric/restmp.html#c1
Theres even a little calculator to check your work.
 
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