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Electrical engineering

Formulas and components

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You can always create as many flashcards as you like, free of charge.

If you would rather use a ready-made deck such as Electrical engineering, we ask you for a small sum in return. For €0.99 once you get 59 flashcards, sorted into 7 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.

Cards
59
Categories
7
Price
€0.99

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What is in this deck

With this deck you learn the basics of electrical engineering: components, voltage, current and resistance, plus the formulas for power and energy.

Everyone knows U equals R times I. But which quantity is measured in farads, why is parallel resistance smaller than the smallest single one, and what does a residual-current device protect against?

12 formulas in three directions and 12 components in two.

Formulas are the same in every language; the names of the quantities and the meaning of the symbols are translated.

The categories decide what comes up: start with “Alternating current” alone and add the rest when you are ready.

What you learn

  • Ohm's law, power, series and parallel
  • Volt, ampere, ohm, watt, farad and hertz
  • Fuse, earthing and residual-current protection

The categories

7 categories sort the 59 cards. You can filter by category and take on what is due right now.

  1. Alternating current
  2. Basic quantities
  3. Circuits
  4. Components
  5. Current and voltage
  6. Power and energy
  7. Protection and safety

What you get

Here are three of the 59 cards you get when you buy the deck.

  1. Question

    How do you calculate voltage?

    Answer

    U = R · I

    Note

    R is resistance, I is current. Ohm's law.

  2. Question

    Which quantity do you calculate with U = R · I?

    Answer

    voltage

    Note

    R is resistance, I is current. Ohm's law.

  3. Question

    In which unit is voltage measured?

    Answer

    V

    Note

Learning with Qardbox

You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.

What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.

Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.

What it costs, and what it doesn’t

Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.

Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.

It is a shortcut: 59 checked cards for €0.99, once, with Family Sharing. The work you would otherwise do is already done. The App Store shows the price in your currency.

Common questions

Do I have to pay for Qardbox?

No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €0.99 once.

Could I make these cards myself?

Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.

How many cards are in Electrical engineering?

59 cards, sorted into 7 categories.

Do I need a connection to study?

Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.

Which devices does this run on?

On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.

Is there a Qardbox for Android?

No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.

Get started

Get Qardbox, look at the deck in the store and decide there. The app is free whether you take this deck or not.

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