Fill in the blank:1- Lap winding is suitable forcurrent,voltage d.c. generators.2- A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torqueproduced when the armature current is 20 A, is --------- N-m.3- The d.c. series motor should never be switched on at no-load because4- The equation relating the generated c.m.f., E, terminal voltage, armature current andarmature resistance for a d.c. motor is E =5- A transformer having 1000 primary turns is connected to a 250 V a.c. supply. For asecondary voltage of 400 V, the number of secondary turns should be turns.6- The equivalent resistance of the primary of a transformer having N2/N1 = 5 and R1 = 0.1ohm when referred to secondary becomesohm..057- The maximum efficiency of a 100 kVA transformer having iron loss of 900 W and F.L.cu loss of 1600 W occurs at -------KVA.650KVA8- If Cu loss of a transformer at 7/8 full load is 4900 W, then its full-load Cu loss would be---- watt.‒‒‒‒‒‒‒

Fill in the blank: 1- Lap winding is suitable for --- -current, --voltage d.c. generators. 2-A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torque produced when the armature current is 20 A, is -----N-m. 3- The d.c. series motor should never be switched on at no-load because 4- The equation relating the generated c.m.f., E, terminal voltage, armature current and armature resistance for a d.c. motor is E=

Fill in the blank: 1- Lap winding is suitable for --- -current, --voltage d.c. generators. 2-A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torque produced when the armature current is 20 A, is -----N-m. 3- The d.c. series motor should never be switched on at no-load because 4- The equation relating the generated c.m.f., E, terminal voltage, armature current and armature resistance for a d.c. motor is E=

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter33: Single-phase Motors

Section: Chapter Questions

Problem 32RQ

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