Two long straight parallel wires separated by a distance of 20 cm carry currents of 30 a and 40 a in opposite directions. what is the magnitude of the resulting magnetic field at a point that is 15 cm from the wire carrying the 30-a current and 25 cm from the other wire?

Explanation:

Magnetic field due to straight long wire is always perpendicular to the line joining the wire and the point

it is given by the equation

now the magnetic field due to 30 A current is given as

Now magnetic field due to other wire having current 40 A is given as

now net field along Y direction is given as

now for X direction magnetic field we know

Now net magnetic field is given as

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