What is "Apparent Power" (VA)?

[iScience]

In school I learned about impedance:
where..

$$Z^2 = R^2 + X_{net}^2$$

but this was the only triangle I recall learning about.
The picture below I definitely do not recall.

from this Link

The only quantity I am familiar with is the x-axis (Power).

If someone could explain apparent power and its importance with finding an appropriate UPS device, please throw me a bone. ty

 

[gleem]

See this article: http://edistoelectric.com/understan...its both,poor utilization of electrical power.

 

[anorlunda]

Read that article that @gleem posted for you.

For a dead simple example, a 100 VA UPS could power a 100 w resistance heater, but not a 100 w motor. That's why it is important.

In a resistance, the imaginary power is zero, so VA and power are the same thing. That's what you are used to.

The motor needs both real power (watts) and imaginary power, so the VA is the complex sum as shown in the diagram you posted in #1.