Did you know Why Ferrite bead is connected to your laptop power cable ?
Most people see the cylinder of their laptops but they have no idea why it is for. Some believes it is only for decoration. But
Actually it is called ferrite bead, ferrite core or a choke in general. it is nothing but a inductor which suppress high frequency noises in electronic circuits.
The cables of charger can act like unidirectional antennas, broadcasting electrical interference (noise). They can generate EMI ( Electromagnetic interference) and RFI (radio frequency interference). The appointed task of ferrite core is to prevent such interference.