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

Answer:

The resistance of the coil is 4 Ω.

Explanation:

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

$R = \frac{\rho L}{A}$

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:          

$R = \frac{\rho L}{A} = \frac{0.02 \cdot 10^{-6} \Omega m*160 m}{8 \cdot 10^{-7} m^{2}} = 4 \Omega$

Therefore, the resistance of the coil is 4 Ω.

                                       

I hope it helps you!