Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Scientists Study "Frictional Ageing" - Standing Objects Becoming Harder to Move

dryriver (1010635) writes | about 2 years ago

Science 1

dryriver (1010635) writes "The BBC reports: 'Have you ever had the impression that heavy items of furniture start to take root – that after years standing in the same place, they’re harder to slide to a new position? Do your best wine glasses, after standing many months unused in the cabinet, seem slightly stuck to the shelf? Has the fine sand in the kids’ play tray set into a lump?

If so, you’re not just imagining it. The friction between two surfaces in contact with each other does slowly increase over time. But why? A paper by two materials scientists at the University of Wisconsin in Madison, USA, suggests that the surfaces could actually be slowly chemically bonding together.

There are already several other explanations for this so-called “frictional ageing” effect. One is simply that two surfaces get squashed closer together. But a curious thing about friction is that the frictional force opposing sliding doesn’t depend on the area of the contacting surfaces. You’d expect the opposite to be the case: more contact should create more friction. But in fact two surfaces in apparent contact are mostly not touching at all, because little bumps and irregularities, called asperities, prop them apart. That’s true even for apparently smooth surfaces like glass, which are still rough at the microscopic scale. It’s only the contacts between these asperities that cause friction.'"

Link to Original Source

Sorry! There are no comments related to the filter you selected.

It's called rust (0)

Anonymous Coward | about 2 years ago | (#41933695)

That's why WD40 was invented.

Check for New Comments
Slashdot Login

Need an Account?

Forgot your password?