# The Googol Gears (DD-327)

> A googol is 1 followed by 100 zeros. Daniel de Bruin built a gear machine to make that number tangible: a chain of 100 gear stages, each reducing speed by a factor of ten, driven by a hand crank. The first gear spins freely, but the final gear would need a googol turns of the crank to rotate once, far longer than the age of the universe at any practical speed. The footage shows the long row of gears.

- Department: Tech (also Science)
- First published: 2024-09-20
- Last updated: 2024-09-20
- Permalink: https://detailenjoyer.com/case/the-googol-gears/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-327-F01**: A googol is 10 to the 100th. _(Write-up · Exhibit A (Googol))_
- **DD-327-F02**: Gears can reduce speed. _(Write-up · Exhibit B (Gear train))_

## Write-up

Each gear turns ten times slower than the one before it. With 100 steps, the last gear would need a googol turns of the crank.

1. **Googol**: A googol is 10 to the 100th.
2. **Gear train**: Gears can reduce speed.
3. **Ten to one**: Each stage slows motion tenfold.
4. **Builder**: Daniel de Bruin built it.
5. **Last gear**: The last gear effectively never turns.

## Reel vs. record

- **Note**: None needed.

## Video: The Googol Gears: Each Gear Turns Ten Times Slower Than the One Before It

- Duration: 28.8 s · Published: 2024-09-20
- File: https://detailenjoyer.com/assets/videos/DAKTMQmJH1K.mp4

### Transcript

Did you know, Daniel de Bruin's googol Gear System is an extraordinary mechanical creation designed to visualize the enormous number of googol, which is one followed by 100 zeros. The system consists of a vast array of interconnected gears, with each one turning more slowly than the previous one. It starts with a hand-crank gear, and as the motion transfers through the series, the final gear would take an almost incomprehensible amount of time to complete a single rotation, longer than the lifespan of the universe. This system is a striking demonstration of scale, time, and the intricacies of mechanical motion. NOW YOU KNOW!

## Questions & answers

**Q: What is a googol?**  
A: 10^100. _(Source: Write-up · Exhibit A (Googol) · Wikipedia: Googol)_

**Q: How does each gear compare?**  
A: Reduction. _(Source: Write-up · Exhibit B (Gear train) · Wikipedia: Gear train)_

**Q: What drives the machine?**  
A: Turned by hand. _(Source: Write-up · Exhibit C (Ten to one) · Wikipedia: Gear train)_

**Q: Does the last gear visibly turn?**  
A: Effectively never. _(Source: Write-up · Exhibit D (Builder) · Wikipedia: Googol)_

**Q: Who built it?**  
A: An engineer. _(Source: Write-up · Exhibit E (Last gear) · Wikipedia: Googol)_

## Sources

- [Wikipedia: Googol](https://en.wikipedia.org/wiki/Googol)
- [Wikipedia: Gear train](https://en.wikipedia.org/wiki/Gear_train)

## Cite this case file

Easterling, Marcus. "The Googol Gears." The Detail Department (DetailEnjoyer), case file DD-327, last updated Sep 20, 2024. https://detailenjoyer.com/case/the-googol-gears/