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The Ultimate Combination Locks Quiz
by Staff
Combination locks -- the keyless lock on your gym locker or the more complex ones found on safes -- are a very effective way of securing your belongings without the risk of losing a key. You turn the dial this way and that way, and eventually the lock opens. Wouldn't you like to know what's happening inside the lock? Take this quiz to learn more about how combination locks work.

The wheel pack design used in modern combination locks has been around for how long?

  • 100 years
  • 300 years
  • 500 years

The combination dial is which part of the lock mechanism?

  • The dial with the numbers on it is the combination dial.
  • The combination dial is the set of gears inside the lock.
  • The thin metal pin that turns all of the gears is the combination dial.

Which of these statements best defines a wheel pack?

  • A wheel pack is the latch that locks the door of a safe.
  • A wheel pack is a set of gears that make up the opening mechanism of a combination lock.
  • A wheel pack is a set of four locks sold at a discount price.

The combination dial is attached to which of these?

  • the drive cam
  • the wheel fly
  • the spindle

What determines how many wheels there will be in a wheel pack?

  • There will be as many gears in the wheel pack as there are numbers in the combination.
  • A combination lock always has five wheels in the pack.
  • Every manufacturer uses a different number of wheels in their wheel packs.

The tab that extends outward from a gear wheel is called what?

  • fence
  • drive pin
  • wheel notch

As a gear turns, its drive pin is caught by another small tab known as what?

  • drive pin
  • fence
  • wheel fly

Each wheel has a small gap in its perimeter known as what?

  • a gear gap
  • a wheel notch
  • a lock slit

Which of these is likely to have a locking mechanism with a fence?

  • a small pad lock
  • a safe
  • an electromagnetic vault

What happens to a combination lock's fence once the wheel notches line up?

  • It will fall into the resulting gap and out of the way of the lock's bolt, thus unlocking the safe.
  • It will slide out of the safe, allowing the door to open.
  • It will break, and allow the safe to open.