DC motors are usually seen in applications where the motor speed needs to be externally controlled. AC motors work best in applications where power performance is sought for extended periods of time. All DC motors are single phase, but AC motors can be single phase or three phase.
AC and DC motors use the same principle of using an armature winding and magnetic field except with DC motors, the armature rotates while the magnetic field doesn’t rotate. In AC motors the armature does not rotate and the magnetic field continuously rotates.
In some applications today, DC electric motors are replaced by combining an AC electric motor with an electronic speed controller, known as variable frequency drives. DC electric motors are replaced with an AC electric motor and an electronic speed controller because it is a more economical and less expensive solution.
DC electric motors have many moving parts that are expensive to replace, and DC electric motor repair is usually more expensive than using a new AC electric motor with an electronic controller.
In our experience, combining an AC motor and drive proves to be the most cost effective solution for mostapplications. When servicing our customers in the field, we often recommend looking at the SMVector Series Variable Frequency Drive in combination with a three phase AC motor.
Answer:
The theory of marginal analysis states that whenever marginal benefit exceeds marginal cost, a manager should increase activity to reach the highest net benefit. ... Sunk costs, fixed costs, and average costs do not affect the marginal analysis. They are irrelevant to future
Explanation:
I do have AP world history
The answer could be Leptospirosis
Answer: Cognitive
Explanation:
Cognitive psychology focuses on the mind and the processes involved therein. It focuses therefore on mental processes which include but are not limited to, attention, memory, thought process and creativity.
Popular cognitive psychological disorders include amnesia, dementia and depression. Given that there is medicine that is aimed at slowing memory loss in the case of dementia and antidepressants for depression, it can be surmised that from a Cognitive perspective, medication can be recommended by a psychologist.
