A solenoid coil has 10 turns per cm along its length and a cross secti...
n1=10 turns per cm, =1000 turns per metre
n2l=100, A=10 c=0.1 m2, M=μ0n1(n2l) A
=4πx10-7×1000×100×0.1H=0.13mh
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A solenoid coil has 10 turns per cm along its length and a cross secti...
Calculation of Mutual Inductance between Two Coils
Given:
- Number of turns per unit length of the first solenoid coil = 10 turns/cm
- Cross-sectional area of the first solenoid coil = 10 cm²
- Number of turns of the second wire wound around the first solenoid coil = 100 turns
- The two coils are electrically insulated from each other.
To find:
- The mutual inductance between the two coils.
Solution:
Step 1: Calculation of the magnetic field produced by the first solenoid coil
The magnetic field produced by the first solenoid coil can be calculated using the formula:
B = μ₀nI
where B is the magnetic field, n is the number of turns per unit length, I is the current passing through the solenoid, and μ₀ is the permeability of free space.
Here, n = 10 turns/cm = 10,000 turns/m
Cross-sectional area of the solenoid coil = 10 cm² = 0.001 m²
Number of turns in the solenoid coil = length of the solenoid x number of turns per unit length
= 0.1 m x 10,000 turns/m
= 1000 turns
Therefore, the current passing through the solenoid coil can be calculated as:
I = B/(μ₀n) x cross-sectional area of the solenoid coil
= 10^(-4) T/(4π x 10^(-7) Tm/A) x 0.001 m²/(10,000 turns/m)
= 7.96 A
Step 2: Calculation of the magnetic flux produced by the first solenoid coil
The magnetic flux produced by the first solenoid coil can be calculated using the formula:
Φ = B x A
where Φ is the magnetic flux, B is the magnetic field, and A is the cross-sectional area of the solenoid coil.
Here, B = 10^(-4) T and A = 0.001 m²
Therefore, the magnetic flux produced by the first solenoid coil can be calculated as:
Φ = 10^(-4) T x 0.001 m²
= 10^(-7) Wb
Step 3: Calculation of the mutual inductance between the two coils
The mutual inductance between the two coils can be calculated using the formula:
M = NΦ₂/I₁
where M is the mutual inductance, N is the number of turns of the second wire wound around the first solenoid coil, Φ₂ is the magnetic flux produced by the second wire, and I₁ is the current passing through the first solenoid coil.
Here, N = 100 turns, Φ₂ = Φ (since the two coils are wound coaxially), and I₁ = 7.96 A
Therefore, the mutual inductance between the two coils can be calculated as:
M = 100 x 10^(-7) Wb/7.96 A
= 1.2566 x 10^(-5) H
= 0.0126 mH
Therefore, the correct option is (
A solenoid coil has 10 turns per cm along its length and a cross secti...
M= (u0* N1*N2*A)/L......here, N1= 10, N2= 100, A= 10*10^-4 m^2, L= (1/100) m...... now put the value.... and M= 0. 13 mH.