Electrical and Mechanical System Analogies

Study Notes

Analogy between Electrical and Mechanical Systems

Electrical systems are compared to mechanical systems, where electricity is like water flowing through a pipeline network
Electrons are analogous to water quantity, measured in Coulombs (C)
Current is equivalent to flow rate, measured in Amperes (A)
Voltage is equivalent to pressure, measured in Volts (V)
Resistance is equivalent to a nozzle or orifice, measured in Ohms (Ω)
Capacitance is equivalent to an accumulator or reservoir, measured in Farads (F)

Current

Current is the amount of electric charge flowing during a unit of time (ΔQ/Δt)
1 Ampere (A) is equivalent to 1 Coulomb per second (1C/s) or 6.24E18 electrons per second
Current density (J) is measured in Amperes per unit area (A/m²)
Ampere is a large unit, so smaller units like milliAmperes (mA), microAmperes (μA), nanoAmperes (nA), and picoAmperes (pA) are commonly used
Examples of current usage: 200mA for mobile phones, μA-pA for low-power microchips, 100mA-1A for cardiac/respiratory arrest, 1A for 100W light bulbs, etc.

Voltage

Voltage is the electromotive force (emf) that pushes free electrons to flow through a conductor
1 Volt (V) is equivalent to 1 Joule per Coulomb (1J/1C) or Power per Current (P/I)
Voltage is measured in Volts (V)
Examples of voltage usage: 1.5V battery can perform 1.5J of work while moving 1C of charge

Laws for DC Circuits

Kirchhoff's Voltage Law: the sum of net voltage in a closed loop is zero (ΣV=0)
Example: for three closed loops, the sum of voltages in each loop is zero

Description

Test your understanding of electrical and mechanical systems by identifying the analogies between them. This quiz covers concepts such as circuit pipelines, electrons, current, voltage, and more. Compare electrical circuits to mechanical systems and see how much you know!