# Shatter & Collide (DD-347)

> A spinning disc is stretched by rotational stress that grows with speed. Polycarbonate CDs are built for drive speeds up to roughly 10,000 rpm; beyond their limits, or when cracked, they can shatter violently, and fast CD-ROM drives occasionally broke damaged discs. Many drives cap speed partly for this reason. The footage shows a CD on a motor spinning until it shatters.

- Department: Tech (also Science)
- First published: 2024-10-18
- Last updated: 2024-10-18
- Permalink: https://detailenjoyer.com/case/shatter-and-collide/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-347-F01**: Stress grows with spin speed. _(Write-up · Exhibit A (Stress))_
- **DD-347-F02**: CDs are polycarbonate. _(Write-up · Exhibit B (Material))_

## Write-up

Spin a CD fast enough and it bursts apart. Cracked or worn discs give way first.

1. **Stress**: Stress grows with spin speed.
2. **Material**: CDs are polycarbonate.
3. **Cracks**: Cracked discs fail sooner.
4. **Drives**: Fast drives broke some discs.
5. **Limits**: Drives limit speed.

## Reel vs. record

- **Note**: None needed.

## Video: Shatter & Collide: Spin a CD Fast Enough and It Bursts Apart

- Duration: 30.6 s · Published: 2024-10-18
- File: https://detailenjoyer.com/assets/videos/DBQOI4cuCH4.mp4

### Transcript

Did you know, CD integrity failure at high speed occurs when a CD spins too fast, often beyond its design limits, which can lead to physical damage. As the speed increases, rotational forces put pressure on the CD, which can cause it to crack or even shatter. This is more likely with older or scratched CDs, as structural weaknesses make them less able to withstand the strain. High speed failures are rare with most consumer CD players, as they usually limit speed to safe levels. However, some high speed computer drives or industrial CD testing equipment can potentially cause integrity failures if not properly regulated. NOW YOU KNOW!

## Questions & answers

**Q: What breaks the disc?**  
A: Speed. _(Source: Write-up · Exhibit A (Stress) · Wikipedia: Compact disc)_

**Q: Which discs fail first?**  
A: Weak points. _(Source: Write-up · Exhibit B (Material) · Wikipedia: Compact disc)_

**Q: What are CDs made of?**  
A: Plastic. _(Source: Write-up · Exhibit C (Cracks) · Wikipedia: Compact disc)_

**Q: Do drives limit speed?**  
A: Safety. _(Source: Write-up · Exhibit D (Drives) · Wikipedia: CD-ROM)_

**Q: What does the footage show?**  
A: Spinning test. _(Source: Write-up · Exhibit E (Limits) · Wikipedia: CD-ROM)_

## Sources

- [Wikipedia: Compact disc](https://en.wikipedia.org/wiki/Compact_disc)
- [Wikipedia: CD-ROM](https://en.wikipedia.org/wiki/CD-ROM)

## Cite this case file

Easterling, Marcus. "Shatter & Collide." The Detail Department (DetailEnjoyer), case file DD-347, last updated Oct 18, 2024. https://detailenjoyer.com/case/shatter-and-collide/