Motors 1

Question 1

Magnetic flux is densest and magnetic force is strongest at the ? of a magnet.

Answer 1

Poles

Question 2

The requirements for induction are: ? , a magnetic field, and relative motion between the conductor and the magnetic field.

Answer 2

A Conductor

Question 3

The ? rule is an explanation of the direction of a magnetic field around a coil relative to the direction of the current in the coil, where a left hand is used to illustrate the relationship.

Answer 3

Left-Hand coil

Question 4

With a DC motor, a ? is used to reverse the current direction, which keeps the current flowing in one direction (DC) through the windings to keep the polarity correct in order to interact with the main fields.

Answer 4

Commutator

Question 5

The ? rating of a motor is abbreviated Hz.

Answer 5

Frequency

Question 6

The power rating is the amount of voltage a motor draws when delivering full rated output.
Select one:

Answer 6

False

Question 7

Which of the following terms does not refer to the amount of current a motor draws on startup or when the rotor is locked?

Answer 7

Closing-Rotor current

Question 8

For integral-horsepower frame sizes, the first two digits of the frame number represent the distance from the bottom of the base to the center of the shaft in 16ths of an inch.

Answer 8

False

Question 9

The speed of a 6-pole AC generator operating on 60 hertz is ? .

Answer 9

1200 RPM

(120*F)/P

F = Frequency
P = Poles

Question 10

Motor power is rated in ? or ? .

Answer 10

Horsepower / Watts

Question 11

The ? provides a short-circuit path for induced current to circulate within a rotor.

Answer 11

Shorting Ring

Question 12

? motors are designed for a broad variety of applications, such as in HVAC applications providing power for fans and blowers and in industrial applications providing power for pumps.

Answer 12

Design B

Question 13

Mutual induction typically requires the presence of a magnetic field without the movement of a conductor within that field.

Answer 13

False

Note: Please note that the motion can be provided by an AC field or by holding the conductors stationary and moving the field as in an alternator. However, typically mutual induction requires the presence of a magnetic field and the movement of a conductor within that field.

Question 14

The left-hand coil rule describes the ? of the magnetic poles created by the current flow.

Answer 14

Polarity

Question 15

The direction of torque in a motor can be determined with the ? rule.

Answer 15

Right Hand Motor Rule

Question 16

The rotor’s magnetic field and the stator’s magnetic field interact to create ? .

Answer 16

Torque