Electrical Engineering: Watts Volts Amps Ohms

Basic Equivalences.

1. Resistance

   • Expressed as Ohms (Ω) below.
   • The aggregate opposition to Charge movement.
   • The opposition to Electrons as they flow through material.

2. Current

   • Expressed as Amps (A) below.
   • Rate of flow of Charge.

3. Voltage

   • Expressed as Volts (V) below.
   • Difference in Electrical Potential.

4. Power

   • Expressed as Watts (W) below.
   • The amount of energy produced or consumed by an electrical device.

Electrons flow through material when there's an imbalance in Electrical Potential (Voltage). They flow at a certain rate (Current) which is modified by Resisting factors that inhibit how the Electrons move.

Ohms Law

• Ω = V / A
• Ω = V² / W
• Ω = W / A²

Amps

• A = V / Ω
• A = W / V
• A = √(W / Ω)

Volts

• V = A * Ω
• V = W / A
• V = √(W * Ω)

Watts

• W = V * A
• W = V² / Ω
• W = A² * Ω

Resources and Links

1. https://www.rapidtables.com/calc/electric/ohms-law-calculator.html
2. https://www.usna.edu/ECE/ee301/Lecture%20Notes/EE301_Lesson_01_Voltage_Current_Resistance_Ohms.pdf

Electrical Engineering: Static Electricity

Electrons, Neutrons, and Protons

1. Electrons - are Negatively Charged Particles since they have a negative net Electrical Charge:
   • 1.602176634 × 10−19 coulomb
2. Neutrons - are Neutrally Charged Particles since they have no net Electrical Charge.
3. Protons - are Positively Charged Particles they have a positive net Electrical Charge.

We usually count the Electric Charge of an Atom by the difference in Electrons and Protons.

Static Electricity

Static Electricity is an imbalance of Electrical Charge between two items (particularly on their surface).

Static Electricity shocks occur when there is:

1. An imbalance of Electrical Charge such that:
   • One touching item is Negatively Charged (has many more Electrons)
   • The other item is Positively Charged (has far fewer Electrons)

Static (Electricity) cling occur when there is:

1. When lightweight items stick to another owing to differences in Electrical Charge.
2. Example: confetti sticking to a plastic balloon.

Static (Electricity) hair raising occur when there is:

1. An excessive amount of positive Electrical Charge since two positively charged items will repel each other.
2. (Two positively charged items will repel each other. Two negatively charged items will repel each other.)

Static Electricity grounding:

1. Using a conductive material to keep a two items at the same, common, balanced, Electrical Charge.
2. To use a conductive cord, wire, or other material to prevent Static Electricity shocks.
   • Commonly involves attaching metal wires to two items and connecting those wires to a ground block, wall, or metal object driven into the ground.

Prevention Techniques

1. Ground items in the manner described above.
2. Avoid certain materials like wool, polypropelene, etc. that have either a tendancy to generate Static Electricity or that lack the intrinsic ability to discharge it (e.g. - because they good insulators).
3. Touch small metal objects frequently and then touch those objects against some grounded item (a metal doorframe, a metal floor lamp, etc.).
4. Increase the amount of humidity in the air (since dry air increases the chance of Static Electricity).
   • This option should be pursued only as a last resort around electronics since humidity can damage sensitive electrical components (water is conductive - see below).

Water Conductivity

1. Contrary to popular misconception, water is typically conductive.
   • First, most potable water contains impurities or other chemical elements that are.
   • Even fairly "pure" water will still be slightly conductive since nearly all naturally occuring chemicals/substances contain isotopes, charged particles, and the like (for example: H+ and OH- ions) which are or can be conductive.

Electrical Engineering: Consumer Battery Care

Surge Protectors

• Always use electronics "behind" a Surge Protector (plugged into a Surge Protector, powered using a Surge Protector).
• Never daisy Surge Protectors (connect one Surge Protector into another).
• Check the maximum Wattage allowed by the Outlet or Wall the Surge Protector is plugged into.

Lithium Batteries

• Commonly: Li-ion.
• Terminals (metal faces) should be covered with tape (electrical, duck, etc.) and shouldn't come into contact with each other or metal.
• Must be recycled.
• Can be flammable and/or dangerous if handled or disposed of incorrectly.

Examples:

• CR2032 - Lithium Ion Coin Button Batteries.
• CR123A - Lithium Ion Camera Batteries.

Akaline Batteries

• Generally safe to throw away but should ideally be recycled.
• Will naturally corrode and decay into harmless powders.

Examples:

• Non-Rechargeable (AA, AAA).

Coin or Button Batteries

• Terminals (metal faces) shouldn't come into contact with each other or metal (regardless of their being Lithium Ion or not).
• They ideally should be separated and not stacked one on top of the other without a physical divider.

Rechargeable Batteries

• Typically, Lithium Ion- or NiMH- based.
• Terminals (metal faces) shouldn't come into contact with each other or metal (regardless of their being Lithium Ion or not).
• Must be recycled.
• Can be flammable and/or dangerous if handled or disposed of incorrectly.

Examples:

• Nickel-Metal Hydride (NiMH).
• Lithium Iron Phosphate (LiFePO4).
• Panasonic Eneloop (NiMH) Rechargeable AA, AAA.

Resources and Links

1. https://ring.com/support/articles/d46gw/Replacing-batteries-in-Ring-Alarm-devices