Book 27, Question 123 · Video
Why do some watches say they have jewels?
In old-fashioned mechanical watches, tiny gears spin on pivots. To reduce friction and wear, makers set tiny bearings made of ruby in the places where the pivots turn. Rubies are extremely hard and smooth. Early watches used natural stones, but today the rubies are lab-grown. A watch that says 17 jewels means it has seventeen of these tiny bearings.
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What Crafty Clover says in this video
Intro
Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do some watches say they have jewels?
The Big Idea
Some fancy watches say they have jewels! Are they decorations? No, they do a job!
Spinning Gears
Step one: Spinning Gears. In old-fashioned mechanical watches, tiny gears spin on pivots. To reduce friction and wear, makers set tiny bearings made of ruby where the pivots turn.
Hard and Smooth
Step two: Hard and Smooth. Rubies are extremely hard and smooth. Early watches used natural stones, but today the rubies are lab-grown.
17 Jewels
Step three: 17 Jewels. A watch that says 17 jewels means it has seventeen of these tiny bearings. Each one helps the watch run smoothly for years.
A Closer Look
Let's take a closer look! Gears spin. Pivots turn. Rubies hold them. Friction drops.
Quick Facts
Quick facts! A bearing is a part that lets something turn smoothly. Rubies are hard. Today they're lab-grown. Less friction, less wear.
Think Like a Scientist
Now, think like a scientist! Look at a gear toy. Turn the gears slowly. Find where parts rub. How could you reduce friction there? Write down your ideas.
Outro
Watches with jewels have tiny ruby bearings where gears spin on pivots. Rubies are extremely hard and smooth, so they reduce friction and wear. Today they're lab-grown, and 17 jewels means 17 bearings. Tiny gems, big job. Clever, right? Science is amazing! Remember, every big discovery starts with a small question. Keep looking, keep learning, and keep asking why! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!