Answer:
0.047 T
Step-by-step explanation:
When a current-carrying wire is placed in a region with a magnetic field, the wire experiences a force, given by the equation

where
I is the current in the wire
L is the length of the wire
B is the strength of the magnetic field
is the angle between the direction of B and I
In this problem:
L = 1.50 m is the length of the wire
I = 10.0 A is the current in the wire
F = 0.70 N is the force exerted on the wire
since the current is at right angle with the field
Solving for B, we find the strength of the magnetic field:
