Traffic Light — Questions and answers

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What was London like before traffic lights were invented, according to Sir John Peake Knight?

Choices

  1. It was peaceful and quiet.
  2. It was a chaotic and dangerous mix of people and vehicles. ✓
  3. It had too many parks and not enough roads.
  4. It had flying cars everywhere.

Answer: It was a chaotic and dangerous mix of people and vehicles.

From page 1

What was the main problem with Sir John Peake Knight's gas-powered semaphore?

Choices

  1. It was too quiet.
  2. It ran out of gas too quickly.
  3. Using an open flame near gas was dangerous at night. ✓
  4. It only worked during the day.

Answer: Using an open flame near gas was dangerous at night.

From page 3

Why did Lester Wire think electricity was better for traffic signals than gas?

Choices

  1. Electricity made the lights sing.
  2. Electricity was safer and brighter, without open flames. ✓
  3. Electricity was only found in Salt Lake City.
  4. Electricity could make the signals float.

Answer: Electricity was safer and brighter, without open flames.

From page 4

What was the main benefit of the three-color traffic lights, according to the Cleveland police chief?

Choices

  1. They made streets look prettier.
  2. They caused more confusion.
  3. Accident rates at intersections went down a lot. ✓
  4. They made cars go faster.

Answer: Accident rates at intersections went down a lot.

From page 8

What does it mean to create a "green wave" with traffic lights?

Choices

  1. Painting all traffic lights green.
  2. Making sure cars can drive through many intersections without stopping. ✓
  3. Only having traffic lights near the ocean.
  4. Having lights that change color randomly.

Answer: Making sure cars can drive through many intersections without stopping.

From page 9

What new technologies do modern traffic light systems use today to adjust to traffic?

Choices

  1. Magic spells and crystal balls.
  2. Advanced sensors, artificial intelligence, and real-time data. ✓
  3. Old fashioned clocks and timers.
  4. Only the sun and moon.

Answer: Advanced sensors, artificial intelligence, and real-time data.

From page 10