Why constantan or manganin wire is used in meter bridge?
Table of Contents
- 1 Why constantan or manganin wire is used in meter bridge?
- 2 What is manganin wire used for?
- 3 What is meter bridge made of?
- 4 Which wire is used in meter bridge?
- 5 What is manganin and constantan?
- 6 Why is a wire bridge not made of copper wire?
- 7 What are the two properties of the wire used in meter bridge and potentiometer?
- 8 What is the wire of metre bridge made up of why?
Why constantan or manganin wire is used in meter bridge?
Constantan is used for meter bridge wire because its temperature coefficient of resistance is almost negligible due to which the resistance of the wire does not change with increase in temperature of the wire due to flow of current.
What is manganin wire used for?
Manganin foil and wire is used in the manufacture of resistors, particularly ammeter shunts, because of its virtually zero temperature coefficient of resistance value and long term stability. Several Manganin resistors served as the legal standard for the ohm in the United States from 1901 to 1990.
What is meter bridge made of?
The connection between the resistors in the metre bridge is done using thick copper wires. Copper has very low resistivity. By using thick copper wires the resistivity is reduced further. Thick copper wires have a larger area and the resistance of wire becomes negligible.
Why manganin wire is used in Carey Foster bridge?
The material of wire used in meter bridge is made of manganin or eureka due to there high specific resistance or resistivity. Thick copper strips are used in meter bridge because copper is a good conductor of electricity.
What is constantan wire?
A constantan wire is a wire made up of copper-nickel alloy. It usually consists of 55\% copper and 45\% nickel. It has a number of special characteristics due to which it is known as the most versatile alloy available. Therefore, a constantan wire is essentially an electrical resistance wire that can be used for heating.
Which wire is used in meter bridge?
In a metre bridge, wires of nichrome, manganin and constantan are used because it has high resistance and low-temperature coefficient of resistance.
What is manganin and constantan?
The alloys manganin and constantan are used for making standard resistance coils as they have high resistivity, low-temperature coefficient of resistance, ability to attain good resistance values in small size. Their resistance value would change very little with temperature.
Why is a wire bridge not made of copper wire?
a) The resistivity of copper wire is very low. The connections between the resistors are made of thick wires so as to increase the rate of cross-section. Therefore, the resistance of wires is almost negligible.
Why thick copper wires are used in a slide wire bridge?
Answer: The connections are made of thick copper wires to minimize the resistance of connecting wires. Because the connection resistance have not been accounted in the formula, (v Resistance is inversely proportional to cross-sectional area, so thick wire has low resistance).
What is the difference between Carey Foster bridge and meter bridge?
The Carey Foster bridge is a modified form of the meter bridge in which the effective length of the wire is considerably increased by connecting a resistance in series with each end of the wire. This increases the accuracy of the bridge.
What are the two properties of the wire used in meter bridge and potentiometer?
The wire which is used in Meter Bridge must have these properties: -Wire must have high specific resistance. -Low temperature coefficient of resistance. High resistance wire is used because if resistance is very high then current will be very low.