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This is my paperwork. It's what I write down the second the clock starts, before I touch a single question — the two wheels and the formulas. Make your worksheet look just like this every time you study and do math, and on test day it just falls out of your hand. You're not remembering formulas under stress; you're already set up, just working the problem.

Free Test-Day Worksheet — Ohm's Law & Power Wheels

Ohm's Law & Power wheels · voltage-drop formulas · NEC 2023
EVoltsICurrent(Amps)RResistance(Ohms)
Ohm's Law
PPower(watts)ICurrent(Amps)EVolts
Power
Single-phase voltage dropVD = (2 × ohms × amps × distance) ÷ 1000
Three-phase voltage dropVD = (2 × ohms × amps × distance × 0.866) ÷ 1000
Horsepower to watts1 HP = 746 W
Square root of 3  (for 3-phase)√3 = 1.732
How to use the wheel: cover the value you want. Ohm's Law — cover E and you see I×R (multiply); cover I and you see E over R (divide); cover R and you see E over I. The Power wheel works the same way with P, I, and E.
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What this worksheet is

This free test-day worksheet is the paperwork I set up the moment the exam clock starts, before I look at a single question. Two wheels and a short list of formulas. It takes about ninety seconds to write out, and from then on I am not trying to remember anything under pressure — I am just working the problem in front of me.

What is on it

How to actually use it

Do not save it for test day. Write it out every single time you sit down to practise, on a blank sheet, from memory. Do that for a couple of weeks and on the real day it falls out of your hand without you thinking about it. Practising the setup is the point — not the sheet itself.

You do not bring this into the exam. You write it out on the scratch paper they give you once the clock has started. What that scratch paper looks like varies — some testing centres hand you a laminated board and a marker, some give you paper — so ask your testing company what they provide when you book, and practise on the same thing.

Why it works

Nearly every calculation question on a journeyman or master exam is one of a small number of shapes. The trouble is almost never the arithmetic — it is deciding whether to multiply or divide while the clock runs and you are second-guessing yourself. The wheels take that decision away. You cover the value you want and the picture tells you.

More free things: try the practice test the way it works inside the course, or read how to look up a code fast. There is also a free 15-question test on the home page — and every question in the course can be read out loud to you.

Free printable from the NEC 2023 Journeyman & Master Electrician study guide. © Kevin's Electrical Prep Course LLC.