What current must flow in an infinitely long straight wire to produce a magnetic field of `4xx10^5T` at `8cm` away from the wire?

Answer

`16A`

Explanation

Here, `I=?, B=4xx10^-5T, r=8xx10^-2m`
`B=(mu_0)/(4pi)(2I)/(r)` or `4xx10^-5=(10^-7xx2xxI)/(8xx10^-2)`
or `I=(8xx4xx10^-7)/(2xx10^-7)=16A`