Alternating Current System — Questions and answers

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What was the biggest problem with Direct Current (DC) electricity that Thomas Edison faced?

Choices

  1. It was too dangerous for homes.
  2. It only worked in the daytime.
  3. It lost too much power when sent over long distances. ✓
  4. It made lamps flicker too much.

Answer: It lost too much power when sent over long distances.

From page 1

Why did George Westinghouse think Edison's DC system was "uneconomical" or too expensive?

Choices

  1. It used too much coal to make electricity.
  2. It required many small power stations close to homes, and a lot of expensive copper wire. ✓
  3. It broke down too often and needed constant repairs.
  4. It didn't make enough light for city streets.

Answer: It required many small power stations close to homes, and a lot of expensive copper wire.

From page 2

What big new idea did Nikola Tesla have for how electricity could work?

Choices

  1. He wanted to make electricity from sunlight.
  2. He thought electricity could flow only in one direction, but faster.
  3. He imagined electricity that could reverse its direction rhythmically to create a rotating magnetic field. ✓
  4. He wanted to store electricity in giant batteries underground.

Answer: He imagined electricity that could reverse its direction rhythmically to create a rotating magnetic field.

From page 3

What were some of the tough problems Tesla and Westinghouse had to solve when building the new AC system?

Choices

  1. They couldn't find enough copper wire to use.
  2. The lights they made were not bright enough.
  3. They had issues with insulating high voltages, preventing overheating, and making sure all parts worked together perfectly. ✓
  4. The system was too loud and scared people away.

Answer: They had issues with insulating high voltages, preventing overheating, and making sure all parts worked together perfectly.

From page 4

What was a big advantage of Tesla's AC induction motor compared to older DC motors?

Choices

  1. It was much smaller and lighter.
  2. It didn't make any noise when it ran.
  3. It didn't need brushes or commutators, which meant less maintenance and more reliable power. ✓
  4. It could run on water instead of electricity.

Answer: It didn't need brushes or commutators, which meant less maintenance and more reliable power.

From page 7

What was the "War of the Currents" mostly about?

Choices

  1. A fight over who invented the light bulb.
  2. Thomas Edison trying to make people scared of AC electricity, even though AC had many benefits. ✓
  3. A disagreement about how much electricity should cost.
  4. A debate about whether electricity should be used in homes or just factories.

Answer: Thomas Edison trying to make people scared of AC electricity, even though AC had many benefits.

From page 8

What big project showed everyone that Alternating Current (AC) could send power very far away?

Choices

  1. Lighting up the Eiffel Tower for the first time.
  2. Sending electricity from New York to California.
  3. Using the power of Niagara Falls to send electricity over twenty miles to Buffalo. ✓
  4. Building the first electric train.

Answer: Using the power of Niagara Falls to send electricity over twenty miles to Buffalo.

From page 9

What is the most important way Alternating Current (AC) helps our world today?

Choices

  1. It helps us send messages across the ocean.
  2. It powers almost everything in our modern world, from big factories to tiny computers. ✓
  3. It helps us build faster cars.
  4. It keeps our food fresh in refrigerators.

Answer: It powers almost everything in our modern world, from big factories to tiny computers.

From page 10