Question

A coil consists of 200 turns of copper wire and have a cross-sectional area of 0.8 mmm square.The mean length per turn is 80 cm and the resistivity of copper is 0.02μΩm at normal working temperature.Calculate the resistance of the coil

Answer 1

The resistance of the coil is 4 Ω.

Step-by-step explanation:

The resistance (R) of the coil can be calculated using the following equation:

`R = (\rho L)/(A)`

Where:

ρ: is the resistivity of copper = 0.02x10⁻⁶ Ωm

L: is the length of the coil

A: is the cross-sectional area = 0.8 mm² = 8x10⁻⁷ m²

The length of the coil is given by:

`L = 200 turn* 80 cm/turn = 16000 cm = 160 m`

Now, the resistance is:

`R = (\rho L)/(A) = (0.02 \cdot 10^(-6) \Omega m*160 m)/(8 \cdot 10^(-7) m^(2)) = 4 \Omega`

Therefore, the resistance of the coil is 4 Ω.

I hope it helps you!