Question

A 0.750-m-long section of cable carrying current to a car starter motor makes an angle of 60º with the Earth's 5.50×10^-5T field. What is the current when the wire experiences a force of 7.00×10^-3N?

a) 0.5 A
b) 1.0 A
c) 1.5 A
d) 2.0 A

Answer 1

The current in the wire is 1.0 A. In this problem, the wire carrying current to a car starter motor experiences a force due to the Earth's magnetic field.

Step-by-step explanation:

To find the current, we can use the equation F = BILsinθ, where F is the force, B is the magnetic field strength, I is the current, L is the length of the wire, and θ is the angle between the wire and the magnetic field.

Given that the force is 7.00 × 10-3 N, the magnetic field strength is 5.50×10-5 T, the length of the wire is 0.750 m, and the angle is 60º, we can rearrange the equation to solve for the current:

I = F / (B*L*sinθ) = (7.00 × 10-3 N) / (5.50×10-5 T * 0.750 m * sin(60º)) = 1.0 A

Therefore, the current in the wire is 1.0 A.