What current is necessary to generate a field of 0.20 T inside a solenoid of 300 turns per cm?
A) 530 A
B) 5.3 A
C) 33 A
D) 0.33 A
E) 3.1 A

Question

Quizplus · Accepted Answer

The magnetic field inside a solenoid is given by B = μ₀nI, where μ₀ is the permeability of free space, n is the number of turns per unit length, and I is the current. Rearranging the equation to solve for I, we get I = B/(μ₀n). Substituting the given values, we get I = 0.20 T / (4π × 10⁻⁷ T·m/A × 300 turns/cm) ≈ 5.3 A. Therefore, the best choice is B.

What Current Is Necessary to Generate a Field of 0