Understanding Solids and Liquids

The video explores the concept of solidity, starting with the 1994 Northridge earthquake. It delves into the nature of pitch, a highly viscous liquid, and the world's longest-running experiment at the University of Queensland. The video debunks the myth that glass flows over time, explaining its amorphous solid state. It then examines the Earth's mantle, which, despite being solid, behaves fluidly over geological timescales. The video concludes with a promotion for Audible.

What event in 1994 led to questioning the solidity of the Earth?

• A volcanic eruption

• A hurricane

• A tsunami

• A massive earthquake

What is the viscosity of pitch compared to water?

• 100 times more viscous

• 10 times more viscous

• 1000 times more viscous

• 2.3×10¹¹ times more viscous

What is the world's longest-running lab experiment about?

• The flow of honey

• The viscosity of olive oil

• The dripping of pitch

• The melting of ice

Why are the bottoms of old stained glass windows thicker?

• Glass flows over time

• Glass was installed with the thicker part at the bottom

• Glass contracts with cold

• Glass expands with heat

What type of solid is glass classified as?

• Amorphous solid

• Ionic solid

• Crystalline solid

• Metallic solid

What is the state of the Earth's mantle?

• Liquid

• Gas

• Plasma

• Solid

How do we know the mantle is solid?

• It is visible from space

• Shear waves can propagate through it

• It conducts electricity

• It emits light

What happens to atoms in the mantle under high pressure?

• They fill gaps in the crystal structure

• They evaporate

• They become liquid

• They form a gas

What did Grove Karl Gilbert say about rigidity and plasticity?

• They are the same

• They are relative terms

• They are absolute terms

• They are unrelated

What is the main message of the final section?

• Glass is a liquid

• The Earth's core is solid

• Definitions of solids and liquids can be fluid

• Solids and liquids are clearly defined