Power transformers are designed to have maximum efficiency at
A). nearly full load
B). 70% full load
C). 50% full load
D). no load
1. The critical pressure ratio of a convergent nozzle is defined as
3. The operating point is also called the ___________
4. The resolution limit of electron microscope is
5. A Buchholz relay can be installed on
6. To increase the current in a series RL circuit, the frequency
7. An induction motor is identical to
8. The number of protons in a copper atom are
9. Any externally introduced signal affecting the controlled output is called a