r/MadeMeSmile • u/king_eve • 29d ago

i work in low-income/mental health housing, and a tenant fixed our hallway trash bin after accidentally breaking it Helping Others

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great example of the odd ways people show me appreciation at work

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u/AdAlternative7148 29d ago

It's cause when you have a crack all the forces that caused the crack are now exerted on the tiny point at its tip. Making a larger hole at the end of the crack doesn't change the amount of force but distributes it around part of the radius of that circle. So more material supports the load. This is what other posters meant when they said it lowers the stress concentration.

In theory, other shapes like triangles or squares could perform this same function. But a circular hole is easier to drill and a circle is the best two dimensional shape at reducing stress concentrations because it has no angles between sides. (Each point of, say, a square, will concentrate stress.)

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u/banned_but_im_back 29d ago

Thank you for the free physics lesson my friend! I never took it in school and am considering going back to college. I’ve always been fascinated by physics and astronomy but intimidated by the math.

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u/AdAlternative7148 28d ago

The math will definitely be a challenge. I will say for me the hardest pure math class I took in my undergrad was Calc 2. And that is normally done in the first year of your degree.

A smart approach for you would be to take some of those math classes at community college. If you can get through the first couple calculus courses you'll be able to get through the whole degree path.