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Refrigeration

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Submitted By LeNyah
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Chapter 17 Lab

1.
When an alternationg current is applied to the running windings of a split-phase electric motor, and alternating current:
A) with the same polarity is induced in the rotor. B) with reverse polarity is induced in the rotor. C) with the same polarity is induced in the start winding. D) circuit to the start winding is opened by the electronic relay.
2.
A two-pole split-phase motor operates at a speed just under:
A) 1800 rpm B) 3600 rpm C) 4800 rpm D) 5200 rpm
3.
A four-pole split-phase motor runs ______________ a two-pole split-phase motor.
A) faster than B) at the same speed as C) slower than
4.
A three-phase power supply can be found in most:
A) homes B) factories C) mobile homes D) recreational vehicles
5.
The electronic relay is used with some electric motors to:
A) provide current to the start windings. B) relay current to the start capacitor C) provide current to the run capacitor D) open the circuit to the start windings after the motor has started
6.
The amount by which the current leads or lags the voltage in an alternating current circuit is know as the:
A) phase angle B) electronic relay C) inductive angle D) starting torque
7.
In an alternating current circuit in which there is a capacitor, the current_____________ the voltage.
A) leads B) lags C) is in phase with D) exponentially is redundant to
8.
The term “slip” is used to indicate:
A) the amount of horsepower lost due to the motor resistance B) the amount of efficiency lost when there is no run capacitor C) the difference in motor rpm between the time the start winding circuit is opened and when the motor reaches full operational speed D) the difference between the motor full operational rpm rating and the actual speed under a load
9.
The hermetic motor must run in a:
A) warm ambient temperature B) refrigerant vapor atmosphere C)

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