A permanent magnet dc commutator motor has a no load speed of 6000 rpm when connected to a 120 V dc supply. The armature resistance is 2.5 ohms and other losses may be neglected. The speed of the motor with supply voltage of 60 V developing a torque 0.5 Nm, is _______ rpm .

A permanent magnet dc commutator motor has a no load speed of 6000 rpm

1.	A permanent magnet dc commutator motor has a no load speed of 6000 rpm when connected to a 120 V dc supply. The armature resistance is 2.5 ohms and other losses may be neglected. The speed of the motor with supply voltage of 60 V developing a torque 0.5 Nm, is _______ rpm .
A.	1337 rpm
B.	2673 rpm
C.	1671 rpm
D.	773 rpm
Answer» C. 1671 rpm

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A permanent magnet dc commutator motor has a no load speed of 6000 rpm when connected to a 120 V dc supply. The armature resistance is 2.5 ohms and other losses may be neglected. The speed of the motor with supply voltage of 60 V developing a torque 0.5 Nm, is _______ rpm .

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