Answer:The magnetic field strength inside a large solenoid is independent of its cross-sectional area.
Step-by-step explanation:
correct answer is "The magnetic field strength inside a large solenoid is independent of its cross-sectional area".
because magnetic field inside a solenoid is given by
![B=\mu _0n i](https://img.qammunity.org/2020/formulas/physics/college/zbbw913df1c2cp6ag5ckbhxuw9qh5fcbms.png)
where i=current in solenoid
also there is highest concentration of magnetic field at the center of solenoid