There is a current I flowing in a clockwise direction in a square loop of wire that is in the plane of the paper. If the magnetic field B is toward the right, and if each side of the loop has length L, then the net magnetic force acting on the loop is:

a. 2ILB

b. ILB

c. IBL2

d. Zero

(d) Zero

Explanation:

Given:

Side of the square, = L

Magnetic field, = B

According to Faraday, the net force acting on a conductor is equal to product of magnetic field, current, length of conductor and sine of the angle between the field and current.

F = BILsinΦ

Where:

B is magnetic field

I is current in the loop

L is length of the loop

Φ is the angle between the magnetic field and current

Φ = 0, since the current and magnetic field are directed in opposite directions.

F = BILsin(0)

F = 0

Therefore, the net magnetic force acting on the loop is zero.

The correct answer is (d) Zero

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it