Variable-frequency drives (VFD) reduce the speed of AC motors by:

A) Applying an adjustable magnetic brake to the motor.
B) Controlling the voltage available to the motor, like a light dimmer.
C) Limiting the current to the motor.
D) Controlling the frequency (Hz) of the power to the motor.


D

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______ is a piece of flat metal that will not rust or deteriorate that covers the point at which the chimney and roof meet.

A. Flashing B. Corbeling C. Capping D. Coping

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What is heat energy that causes a change in state—solid to liquid or liquid to vapor?

a. kinetic energy b. latent heat c. latent heat of fusion d. sensible heat

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Summarize why shielding gas is needed in GMAW welding.

What will be an ideal response?

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The two standard projection methods for creating multiviews are first- and third-angle projection.

Answer the following statement true (T) or false (F)

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