Answer:
15 N
Explanation:
The magnetic force on a piece of current-carrying wire is given by:
[tex]F=ILB sin \theta[/tex]
where
I is the current in the wire
L is the length of the piece of wire
B is the magnetic field strength
[tex]\theta[/tex] is the angle between the direction of B and I
In this problem:
I = 10 A
B = 0.3 T
L = 5 m
[tex]\theta=90^{\circ}[/tex]
Substituting into the equation, we find
[tex]F=(10 A)(0.3 T)(5 m) sin 90^{\circ}=15 N[/tex]