A long solenoid is wound with turns on a cylindrical core of relative permeability

PHYSICS · Subjective · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

40\,\text{cm}

long solenoid is wound with

2000

turns on a cylindrical core of relative permeability

\mu_r = 400

. What current must be passed through the solenoid so that the magnetic field inside it is

0.20\,\text{T}