A PRT consists of 9.0 m of wire of diameter 8.0×10−2 mm. The voltmeter reads 0 V when l1 =0 .44m. If the standard resistor, R, has a resistance of 224Ω, what is the resistivity of platinum?
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PRT? Is that a bridge circuit?
apologies it stands for Platinum Resistance Thermometer.
Given:
L = 9.0 m.
Dia. = 8.0*10^-2 mm = 8.0*10^-5 m.
R = 224 Ohms.
R = p*L/A.
p = A*R/L. = Resistivity.
A = pi*r^2 = 3.14 * (4*10^-5)^2 = 50.3*10^-10m^2.
p = (50.3*10^-10 * 224)/9 = 1.3*10^-7 Ohm-meters.
L = 9.0 m.
Dia. = 8.0*10^-2 mm = 8.0*10^-5 m.
R = 224 Ohms.
R = p*L/A.
p = A*R/L. = Resistivity.
A = pi*r^2 = 3.14 * (4*10^-5)^2 = 50.3*10^-10m^2.
p = (50.3*10^-10 * 224)/9 = 1.3*10^-7 Ohm-meters.
1 answer