Answer / pandi

there is a one way u have to check the rotor if the
commutator and brush assembly present in dc motor but not in
AC motor .

but in size dc motor size quit large compare then Ac motor
and also usually Ac motor has outer cooling fins and blower
which is fixed on shaft in case of dc motor forced air
cooled inside the motor in-order to dissipate the heat .

Answer / jignesh mistry

Ac Motors Body construction is slotted where In Dc motors construction is plain.reasons are given below.
In ac motors armature is static therefor more current for cooling purpose fins are required,thats why on motor body slots are given.
In case of DC Motors Armature is rotating therefor heat produced due to armature current.there for cooling ventilation
is required.and field is static,and it takes very small amount of current so thre is no cooling requirement for that.

Answer / amol dhanbhar

Incase DC motor if u interchange the terminal,motor can be rotate reverse direction vice-versa.
Incase inductions motor if u interchange the terminal, motor can't be reversed

Answer / marippan

Commutator is present even in ac series motor

Answer / gunasekhar

very simple . a DC motor has a commutator which is mounted on
shaft. but induction motor have no commutator . it is
identified by its its winding connections[terminal box]

Answer / swum

dc motors are usually smaller in size compared to ac motors

www.professionaldoordealer.com/articles/2006/05/ac-vs-dc.aspx

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