Alternating current

The video explains how electric charge in alternating current (AC) changes direction periodically, with a frequency of 50 or 60 Hertz. This causes a flicker in fluorescent bulbs. AC is used in power distribution because its voltage can be transformed, allowing electricity to be transmitted over long distances and then reduced to safer levels for use in homes and businesses.

What is the frequency of the alternating current in mains electricity?

• 30 or 40 Hertz

• 70 or 80 Hertz

• 90 or 100 Hertz

• 50 or 60 Hertz

What visual effect can be observed in fluorescent bulbs due to alternating current?

• A color change

• A flicker

• A steady light

• A constant glow

Why is alternating current preferred for power distribution?

• It is cheaper to produce

• It is safer than direct current

• It can be easily stored

• Its voltage can be transformed

How is electricity transmitted over long distances?

• Using batteries

• At high voltage

• Through wireless networks

• At low voltage

What happens to electricity before it is used in homes?

• It is stored in batteries

• It is used at the same high voltage

• It is converted to direct current

• It is transformed to a lower voltage