Quiz #4: Which one is AC?
Which one is AC: a battery, your wall socket, a phone charger's output? (the wall socket)
QUIZ ⚡ Which one is AC?
A) A battery B) Your wall socket C) A phone charger D) All of them
⏱️ 3 seconds… comment your answer before you read on! 👇
✅ Answer: B — the wall socket!
AC (alternating current) swings back and forth:
🌍 230 V · 50 Hz (India, UK, Europe) — 50 back-and-forth cycles every second
🌎 120 V · 60 Hz (USA, Canada) — 60 cycles a second
🔋 A battery gives DC (direct current): one way only (1.5 V for an AA).
🔌 A phone charger takes AC from the wall and turns it into DC for your phone (5 V USB, 9–20 V when fast charging).
Only the wall is AC!
Read the voiceover (transcript)
- Which one is AC? Three seconds!
- Battery, wall socket, or phone charger? Comment your answer!
- It's B, the wall socket! It swings back and forth fifty or sixty times a second.
- Batteries give DC, one way only. Chargers turn AC into DC for your phone.
- Only the wall is AC!
- Next quiz: heater math! Follow for more!
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