Question

The Hall Voltage across a conductor in a 55mT magnetic field is 1.9μV . When used with the same current in a different magnetic field, the voltage across the conductor is 2.8μV .

What is the strength of the second field?

Answer 1

$$B'=B\frac{V'}{V}\\B'=55\frac{2.8}{1.9}=81\ m T$$