Find the magnetic field at point O shown in the figure

Find magnetic field at O.

Find magnetic field at O.

Find the magnetic field B at the point P in figure

Find the magnetic field B at the point P in figure

A charge particle of charge 'q' and mass 'm' enters in a given magnetic field 'B' and perpendicular to the magnetic field as shown in the figure. It enters at an angle of 60^(@) with the boundary surface of magnetic field and comes out at an angle of 30^(@) with the boundary surface of the magnetic field as shown in the figure. Find width 'd' in which magnetic field exist.

Find magnetic induction at point O in the figure-4.32 shown due to the current carrying loop with current/ as shown .

What is the net magnetic field at point O for the current distribution shown here?