Magnetism and machines

Question 1 of 10

A 4-pole AC generator runs at 1,500 rpm. Its output frequency is

Question 2 of 10

Fleming's right-hand rule is used to find the direction of

Question 3 of 10

The part of a DC machine that carries the armature winding and rotates is the

Question 4 of 10

The part of a d.c. motor that reverses the current in the coil every half turn is the

Question 5 of 10

The direction of force on a current-carrying conductor in a magnetic field is given by

Question 6 of 10

Hysteresis loss in a transformer core is reduced by using

Question 7 of 10

The part of a d.c. motor that reverses the current in the armature every half turn is the

Question 8 of 10

The back e.m.f. of a DC motor with supply 240 V, armature resistance 0.5 Ω and current 20 A is

Question 9 of 10

The rule used to find the direction of the induced current in a generator is

Question 10 of 10

Laminating a transformer core reduces