Table of Contents
How do you find the resistance of a constantan wire?
The constant of proportionality R is the resistance of the con- ductor. For a metal wire of length x and cross-sectional area A, the resistance R is given by the following formula: (2) x R A = ρ∙ .
What is the resistance per unit length of a constantan wire?
Material and Shape Dependence of Resistance
Material | Resistivity ρ ( Ω ⋅ m ) |
---|---|
Constantan (Cu, Ni alloy) | 49 × 10−8 |
Mercury | 96 × 10−8 |
Nichrome (Ni, Fe, Cr alloy) | 100 × 10−8 |
Semiconductors |
Does constantan wire have high resistance?
It is better if the alloy used has a high resistivity, since a shorter wire can then be used….Types.
Material | Resistivity (ohm-cmil/ft) | Resistivity (10−6 ohm-cm) |
---|---|---|
Constantan | 272.97 | 45.38 |
Copper | 10.09 | 1.678 |
Iron | 57.81 | 9.61 |
Manganin | 290 | 48.21 |
How does the length of a wire affect resistance experiment?
This is because the free electrons in the wire bump into more atoms, thereby making it harder for electricity to flow. Furthermore, the resistance of a wire is directly proportional to the length and inversely proportional to the area, so doubling the length of a wire should increase the resistance by a factor of two.
How do you find resistance per unit length?
FORMULA:-1) resistance of the wire,R=1/m Where R=resistance of the wire,m=slope of the graph of current versus potential difference. 2)resistance per unit length=R/LWhere L=the length of the experimental wire.
Does a thicker wire have more resistance?
The relationship between resistance and wire length is proportional . The resistance of a thin wire is greater than the resistance of a thick wire because a thin wire has fewer electrons to carry the current. The relationship between resistance and the area of the cross section of a wire is inversely proportional .
What is a resistance of wire?
The resistance of a wire is directly proportional to its length and inversely proportional to its cross-sectional area. Resistance also depends on the material of the conductor. See resistivity. The resistance of a conductor, or circuit element, generally increases with increasing temperature.
How do you find the resistivity of A metal?
Calculate the resistivity using the following equation: o = l/RA. l is the length of the sample (in meters), R is the resistivity (in ohms) and A is the area of the sample (in square meters).
How can we calculate the resistivity of Eureka wire?
Resistivity of eureka =49xx10^(-8) Omegam.
How do you calculate the resistance of a constantan wire?
Take one of the pieces of constantan wire and record its diameter in three places using the micrometer screw gauge. Calculate the average. Set up circuit as shown in the diagram. The Resistance R is the resistance wire (constantan nichrorome) that you will be trying to calculate.
What is the resistance of a 40cm wire?
For example, when the length of the wire is 20cm the resistance is 3.14 ohms; when the length of the wire is 40cm the resistance is 6.18 ohms, which is roughly double.
How do you measure electrical resistance with a multimeter?
Measure each wire by putting the points of both probes to the edges of the wires, and measure them four times/trials each. Record the resistance reading from the multimeter of each of the 5 wires. Average data no. 3: (6.50+7.00+6.50+7.90) ÷ 4 = 6.98 Average uncertainty data of no. 3: (7.90-6.50) ÷ 2 = 0.70
How do you plot the resistance of a wire?
For each wire plot a graph of resistance (y-axis) against length. The resistance of a wire is given by the equation: R = ρ x l/A Where R is resistance, ρ (pronounced ‘rho’) is the resistivity of the wire, l is length and A is its cross-sectional area. The gradient…