phase control:short notes on phase, control
Answers
Answer:
Phase-fired control (PFC), also called phase cutting or "phase angle control", is a method for power limiting, applied to AC voltages. It works by modulating a thyristor, SCR, triac, thyratron, or other such gated diode-like devices into and out of conduction at a predetermined phase of the applied waveform.
Answer:
(i) Environmental aspects must be carefully looked into before building
huge dams.
(11) Most industries are concentrated around coal mines.
(1) Petroleum is referred to as “black gold”.
(iv) Quarrying can become a major environmental concern.
Distinguish between the followings.
(i) Conventional and non conventional sources of energy
(ii) Biogas and natural gas
(iii) Ferrous and nonferrous minerals
(iv) Metallic and nonmetallic minerals