Answer:
Step-by-step explanation:
a )
At a point midway between the wires , magnetic field due to two wires will be equal and opposite so they will cancel each other . Therefore , net magnetic field will be zero .
b )
At a point 25cm to the right of point midway between the wires
distance of this point will be .25 m from one wire and .75 m from other wire .
Magnetic field due to a current carrying wire can be given by the following expression .
B = (μ₀ / 4π ) x 2I / R where I is current and R is distance of the point
= 10⁻⁷ x 2I / R
For the wire at a distance of .25 m
magnetic field B₁ = 10⁻⁷ x 2 x 20 / .25
= 160 x 10⁻⁷ T .
For the wire at a distance of .75 m
magnetic field B₂ = 10⁻⁷ x 2 x 20 / .75
= 53.33 x 10⁻⁷ T .
These fields are opposite to each other , so
net magnetic field = 160 x 10⁻⁷ T - 53.33 x 10⁻⁷ T
= 106.67 x 10⁻⁷ T .
If the wires are horizontal and current is flowing away from the observer , net magnetic field will be in vertically upward direction .
c )
At a point 75cm to the right of point midway between the wires
The point will be .25 m from one wire and 1 .25 m from other wire . And the magnetic field will be aligned in the same direction .
For the wire at a distance of .25 m
magnetic field B₁ = 10⁻⁷ x 2 x 20 / .25
= 160 x 10⁻⁷ T
For the wire at a distance of 1.25 m
magnetic field B₂ = 10⁻⁷ x 2 x 20 / 1.25
= 32 x 10⁻⁷ T
As the fields are aligned in the same direction
Net magnetic field = 160 x 10⁻⁷ T + = 32 x 10⁻⁷ T
= 192 x 10⁻⁷ T .
If the wires are horizontal and current is flowing away from the observer , net magnetic field will be in vertically downward direction.