1.5-m length of straight wire experiences a maximum force of 1.2 N when in a uniform magnetic field that is 1.8 T. 1) What current must be passing through it? (Express your answer to two significant figures.)

 I = 0.44 A

Explanation:

The magnetic force on a conductor is given by the expression

       F = I L x B

Where bold letters indicate vectors, I is the current, L is the vector in the direction of the current, and B is the magnetic field

Since the force is maximum, the wire must be perpendicular to the magnetic field, therefore

        F = I L B sin 90

        I = F / L B

Let's calculate

        I = 1.2 / 1.5 1.8

        I = 0.44 A