How to Escape from a Car Window (SLOW MOTION) - Smarter Every Day 144

TL;DR

Car windows are made with two types of glass - annealed glass for windshields and tempered glass for side windows - to provide safety and prevent injuries during accidents.

Transcript

Hey it's me Destin Welcome back to Smarter Every Day. Have you ever been driving along and you suddenly stop and realize that you're moving around this world in a bubble of glass? It's kind of weird if you think about it. But it's really cool. Engineers have designed the glass in your car to be extremely safe, so that when you have a wreck you decr... Read More

Key Insights

• 😎 Car windshields are made of annealed glass to ensure better visibility and prevent complete shattering during accidents.
• 😒 Side windows use tempered glass to prioritize safety and facilitate escape during emergencies.
• 😎 Rapid cooling in the manufacturing of tempered glass creates tension on the inside and compression on the outside, leading to complete shattering when impacted on the edge.
• 🎠 The use of plastic between glass layers prevents large shards from falling into the car during accidents, reducing the risk of severe injuries.
• 😎 Annealed glass undergoes a slow-cooling process to relieve internal stresses, resulting in slower-cracking glass.
• 😎 Tempered glass releases stress and tension as it continues to break, sometimes producing audible sounds even after initial shattering.
• 😄 Car manufacturers prioritize safety in window design, considering factors such as visibility, shatter resistance, and ease of escape during accidents.

Questions & Answers

Q: Why are car windshields made of annealed glass?

Car windshields are made of annealed glass because it undergoes a slow-cooling process that relieves internal stresses, resulting in slower-cracking glass, ensuring better visibility for the driver. It doesn't completely shatter, preventing potential injuries.

Q: What is the purpose of using tempered glass for side windows?

Side windows are made of tempered glass because it undergoes a rapid-cooling process that creates compression on the outside and tension on the inside. This design allows the glass to shatter completely when impacted on the edge, ensuring the safety of the occupants and facilitating escape during accidents.

Q: Why does the tempered glass shatter when hit on the edge?

Tempered glass shatters when hit on the edge because the rapid cooling process creates tension on the inside and compression on the outside. When this tension is released, the entire sheet of glass is destroyed, causing it to shatter into small, harmless pieces.

Q: How does the use of plastic in car windows enhance safety?

Car windows, especially windshields, have a layer of plastic sandwiched between two sheets of annealed glass. This design prevents large shards from falling into the car during accidents, reducing the risk of severe cuts and injuries to the occupants.

Summary & Key Takeaways

• Car windshields are made of annealed glass, which is heated and cooled gradually to relieve internal stresses, resulting in slow-cracking glass that doesn't completely shatter, ensuring better visibility for the driver.

• Side windows, on the other hand, are made of tempered glass, which is rapidly cooled to create compression on the outside and tension on the inside, causing the glass to shatter completely when hit on the edge.

• Tempered glass is designed to prioritize safety during accidents, while annealed glass provides better visibility and prevents large shards from falling into the car.