a) When it comes to the building of both the DC and the AC generators, the ends of both generator coils are connected to the outer circuit. A DC generator is comprised of two half rings of copper that are connected at their ends to the commutator. In an alternating current generator, the ends of the coil are connected to entire copper rings, which are referred to as slip rings.

b) Heating water in a boiler is accomplished by the use of high-pressure steam generated by thermal power stations, which can be powered by fossil fuels such as coal or natural gas.