Does Obsidian Really Form the Sharpest Edge?

The video explores the sharpness of Flint and Obsidian compared to modern tools. A custom setup is built to test hair splitting with various edges, including a razor blade, chisel, Flint, and Obsidian. The sharpness is quantified using a homemade Bess certified Sharpness Tester and Atomic Force Microscopy. Results show that while Obsidian is sharper, its fragility limits practical use. The video concludes with a discussion on the need for application-dependent sharpness standards.

What is the primary purpose of the custom setup involving a microscope and micrometer stages?

• To measure the temperature of the cutting edge

• To control the alignment and displacement of the cutting edge

• To automate the cutting process

• To enhance the visual clarity of the cutting process

Why is a razor blade used as a control in the initial experiments?

• To ensure the setup is capable of splitting hair

• To test the durability of the setup

• Because it is the sharpest tool available

• To compare with the sharpness of Obsidian

What was the outcome when testing the sharpness of knapped Flint?

• It failed to split the hair

• It successfully split the hair

• It was sharper than the razor blade

• It cut the hair into multiple pieces

What is the function of the Bess certified Sharpness Tester?

• To compare the sharpness of different materials

• To test the durability of the cutting edge

• To quantify the sharpness by measuring force required to cut wire

• To measure the thickness of the cutting edge

Why did the Obsidian perform poorly in the sharpness test?

• The test setup was faulty

• It was not properly aligned

• The edge was too thin and fragile

• It was not sharp enough

What advanced technique is used to measure the edge radius of the cutting tools?

• Electron microscopy

• Atomic force microscopy

• X-ray diffraction

• Laser scanning

What material is used to transfer the shape of the cutting edge for AFM analysis?

• Aluminum

• Lead

• Steel

• Copper

What is the main challenge in using AFM for measuring the cutting edge directly?

• The cutting edge is too large

• The cutting edge is too close to the diffraction limit

• The cutting edge is too opaque

• The cutting edge is too reflective

What does the AFM probe measure when traversing the surface?

• The electrical conductivity of the surface

• The deflection of the probe

• The temperature of the surface

• The color of the surface

What conclusion is drawn about Obsidian's sharpness from the AFM analysis?

• It is the most durable material

• It is ideal for all cutting applications

• It is not as sharp as the razor blade

• It is sharper than the razor blade but too brittle