A student makes a short electromagnet by winding `280` turns of wire around a wooden cylinder of diameter `d=5.0` cm. The coil is connected to a battery producing a current of `3.8` A in the wire. (a) What is the magnitude of the magnetic dipole moment of this device ? (b) At what axial distance `zgtgt` d will the magnetic field have the magnitude `5.0mu` T (approximately one - tenth that of Earth's magnetic field ) ?

Answer

`(a)2.1A.m^(2);(b)44cm`