1. What could be the cause of a loud hum coming from a transformer?
2. How are capacitors broadly categorized? Describe how a DC capacitor would differ from an AC capacitor.
3. What is capacitive reactance?
4. What are the two types of transformers?
5. Explain where single-phase power and three-phase power are normally used.
6. The phase shift factors that affect the power calculation E x I relate to what circuits?
7. What is the impedance of a single-phase inductive circuit having a voltage of 120V and a current flow of 5 A?

from 1609, galileo galilei used the recently invented telescope to observe the sun, moon and planets. he saw the mountains and craters of the moon, and for the first time revealed the planets to be worlds in their own right. galileo also provided strong observational evidence that planets orbited the sun.

his discoveries about the moon, jupiter's moons, venus, and sunspots supported the idea that the sun - not the earth - was the center of the universe, as was commonly believed at the time.galileo turned his gaze toward venus, the brightest celestial object in the sky - other than the sun and the moon.