Power Sources

When a lead-acid storage battery is being charged, a harmful effect to humans is:

Answer

Emission of hydrogen gas.

Charging a lead-acid battery releases hydrogen gas, which is explosive; ventilate the space and keep sparks away.

Source: FCC Element 3 question pool, 3I

Not the answer

  • Emission of chlorine gas.
  • Emission of oxygen.
  • Internal plate sulfation may occur under constant charging.

Practice this

The FCC Element 3 (General Radiotelephone) exam is 100 questions and takes 75 correct — 75% — to pass. Element 1, the other half of the licence, is 24 questions and takes 18 correct. The app’s page carries a free ten-question test drawn from the same bank, marked as you go.

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