Chapter 8
Currents
Name the cross-section for current, the endpoints for voltage and the system receiving electrical energy.
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Charge flow and drift
Derive current from a carrier-density model and distinguish net drift from irregular microscopic motion.
Energy per charge
Use a potential reference and distinguish source e.m.f., terminal p.d. and internal energy transfer.
Electrical power and energy
Derive the three power expressions, identify what is held fixed and calculate energy over a stated interval.
Measure input and useful output
Place meters at the chosen load and compare motor-terminal input with useful lifting work over the same events.