Mechanical Universe

Electromagnetic induction makes it easy and natural to generate alternating current. Use of transformers makes it practical to distribute ac over long distances. Although Nikola Tesla understood all this, Thomas Edison chose not to, and thereby hangs a tale. Alternating current circuits obey a differential equation identical to the harmonic oscillator resonance equation.

Learning Objectives

Be able to state the definition of rms current and relate it to the maximum current in an ac circuit.
Know the phase relationships between voltages and currents for elements of an LRC circuit.
Be able to discuss the relationship between an LRC circuit and a harmonic oscillator.
Be able to describe a step-up and a step-down transformer.
Be able to discuss the relationship between power transmission and voltage.
Be able to state the resonance condition for an LRC circuit and to sketch the power versus angular frequency.