Answer:
30 T
Explanation:
The magnetic field due to first wire at point A is [tex]B_1=\frac{\mu _0i}{2\pi r}[/tex]
Magnetic field due to second wire at point A is [tex]B_2=\frac{\mu _02i}{2\pi r}[/tex]
As the current flows in opposite direction in both the wire so net magnetic magnetic field at point A is [tex]B=B_1+B_2=\frac{\mu _0i}{2\pi r}+\frac{\mu _02i}{2\pi r}=\frac{\mu _03i}{2\pi r}[/tex]
So net magnetic field [tex]B=3B_1=3\times 10=30T[/tex] as [tex]B_1[/tex] is given as 10 T in question