A solenoid contains 300 coils of very thin wire evenly wrapped over a length of 20 cm. Each coil is 0.80 cm in diameter. If this solenoid carries a current of 4.0 A, what is the magnetic field at its center?

Respuesta :

Answer:

The magnetic field at the center of the solenoid is 7.53 mT.

Explanation:

Given that,

Number of turns in the solenoid, N = 300

Length of the wire, L = 20 cm = 0.2 m

Diameter of each coil, d = 0.8 cm                

Radius, r = 0.4 cm

Current in the solenoid, I = 4 A

We need to find the magnetic field at the center of solenoid. We know that the magnetic field is given by the below formula as :

[tex]B=\mu_o nI[/tex]

n is number of turns per unit length

[tex]B=\dfrac{\mu_o NI}{L}[/tex]

So,

[tex]B=\dfrac{4\pi \times 10^{-7}\times 300\times 4}{0.2}\\\\B=7.53\times 10^{-3}\ T\\\\B=7.53\ mT[/tex]

So, the magnetic field at the center of the solenoid is 7.53 mT.