(Solved) The standard resistor is a coil of wire of some alloy having the properties of Which of the above statements are correct?

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 Question :

The standard resistor is a coil of wire of some alloy having the properties of 

Which of the above statements are correct?


(a) Low electrical resistivity and high temperature coefficient of resistance

(b) High electrical resistivity and high temperature coefficient of resistance.

(c) Low electrical resistivity and low temperature coefficient of resistance.

(d) High electrical resistivity and low temperature coefficient of resistance.


Answer : (d) High electrical resistivity and low temperature coefficient of resistance.


Explanation :

Standard resistors are made of very complex alloys. 

These alloys have high electrical resistivity and low temperature coefficient of resistance. So change in resistance of standard resistor with change in temperature should be less. 

Manganin is mainly used to make standard resistance. 

Manganin = (80-85)% cu + (12-15)% Mn + (2-5)% Ni

Manganin is mainly used in electrical precision measuring instruments, shunt multipliers, resistance box, voltmeter, etc

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