Vehicles such as buses may be powered by electric motors. The motors on these
buses use batteries which need to be charged often. This is normally done by
connecting to a fixed electrical supply whilst the bus is parked.
The photograph shows a bus on a road in South Korea. This road enables the
batteries to charge whilst the bus is in motion.
Under the road there are electric cables, connected to a 440V 60 Hz supply. These
generate magnetic fields. There is a coil inside the charging device which is located
below the floor of the bus. This enables the batteries on the bus to charge.