The strength of the magnetic field, if the current is changed to 40 A, is 0.008 T.
Magnetic Field:
The region in a space where the magnetic force is experienced by the particles is known as a magnetic field.
Given data:
The magnitude of current flow is, I = 20 A.
The strength of the magnetic field is, B = 0.004 T.
The expression for the magnetic field around a circular wire of radius r is,
................................................(1)
here,
is the magnetic permeability of free space.
If the current becomes 40 A, then the new magnetic field is given as,
.................................................(2)
Taking the ratio of equation (2) and equation (1) as,
![\dfrac{B'}{B} = \dfrac{I'}{I}\\\\ \dfrac{B'}{0.004} = \dfrac{40}{20}\\\\ B' = 0.008 \;\rm T](https://tex.z-dn.net/?f=%5Cdfrac%7BB%27%7D%7BB%7D%20%3D%20%5Cdfrac%7BI%27%7D%7BI%7D%5C%5C%5C%5C%0A%5Cdfrac%7BB%27%7D%7B0.004%7D%20%3D%20%5Cdfrac%7B40%7D%7B20%7D%5C%5C%5C%5C%0AB%27%20%3D%200.008%20%5C%3B%5Crm%20T)
Thus, we can conclude that the strength of the magnetic field, if the current is changed to 40 A, is 0.008 T.
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