Powering the Grid: Nikola Tesla and the Alternating Current Revolution
Every time you plug a lamp into a wall outlet, an invisible network springs into action. Electricity travels quietly along overhead wires, slips through metal transformers, and delivers power right to your fingertips. Today, our shared electric system relies mostly on alternating current, or AC. In the late nineteenth century, however, whether AC or direct current (DC) would power our world was one of the fiercest debates in science and engineering.
Direct current, championed by Thomas Edison, flows steadily in a single direction, much like water flowing smoothly through a garden hose. While DC worked well for lighting nearby buildings, it faced a serious limitation: it lost energy quickly over long distances. Early DC power plants had to sit within about a mile of the buildings they powered, which meant a large city would need hundreds of noisy, smoking power stations.
- alternating current:
- An electric current that regularly reverses its direction of flow.
- direct current:
- An electric current that flows in only one steady direction.
- transformer:
- A device used to increase or decrease the voltage of an alternating current.
- voltage:
- The electrical force or pressure that pushes electric charges through a wire.
- generator:
- A machine that converts mechanical motion into electrical energy.
- kinetic energy:
- The energy an object or substance possesses because of its motion.
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Preview questions from this passageShowHide
- 1What is the main difference in how electric charges flow in alternating current compared to direct current?
- 2Why was direct current impractical for supplying electricity across an entire large city?
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About this explanatory article passage for Upper Elementary
“Powering the Grid: Nikola Tesla and the Alternating Current Revolution” is a explanatory article reading passage about History of Electric Power Systems, written for Upper Elementary. It takes about 4 minutes to read (595 words) and comes with an interactive quiz and a printable worksheet with comprehension questions and an answer key.