contestada

Two long parallel wires are a distance d apart. The current in one wire is 10 A and the current in the other wire is 30 A. The currents are in the same direction. If the 30-A current is increased to 50 A, by what factor does the magnitude of the magnetic field midway between the wires change?

Respuesta :

Answer:

The magnitude of the magnetic field midway between the wires increased by a factor of  ²/₃ or 67%.

Explanation:

Given;

current in the first wire, I₁ = 10 A

current in the second wire, I₂ = 30 A

magnetic filed produced in the first wire due to the current in the second wire is given as;

[tex]B = \frac{\mu I}{2\pi d }[/tex]

where;

B is the magnetic field

when the current is 30 A, the magnetic field midway between the wires

[tex]B_1 = \frac{30*\mu}{2\pi d/2} = \frac{30*\mu}{\pi d}[/tex]

when the current is increased to 50 A, the magnetic field midway between the wires;

[tex]B_2 = \frac{50* \mu}{2\pi d/2} = \frac{50* \mu}{\pi d}[/tex]

the magnitude of the magnetic field midway between the wires changes by a factor of;

[tex]\frac{B_2}{B_1} = \frac{50*\mu}{\pi d} X \frac{\pi d}{30*\mu} \\\\\frac{B_2}{B_1} = \frac{50}{30} = 1.67 = 167 \%[/tex]

Thus, the magnitude of the magnetic field midway between the wires increased by a factor of ²/₃ or 67%.