Why ac motors are not used in railways?
Ac motor has a low starting torque so that DC series motor used in railways cause DC motor has high starting torque
Some types of dc (direct current) motor can be used to generate dc, in which case they are often called 'dynamos'. Some alternating current (ac) motors can be used to generate ac, in which case they are called 'alternators', but many types will only work as motors. For instance, a squirrel cage ac motor cannot be used as an alternator.
Direct current or DC electric motors work for situations where speed needs to be controlled. DC motors have a stable and continuous current. DC motors were the first and earliest motors used. They were found, however, to not be as good at producing power over long lengths. Electric companies found using DC motors to generate electric did not work because the power was lost as the electric was transmitted. Brush DC motors use rings that…