: Why is it easier to break a big glass marble ball by dropping it compare to a small glass marble ball ?
In: Physics
In both cases the impact is focused on a very small area, the larger marble has more weight and so more force being focused against that area.
**force = mass * acceleration**
gravity makes everything **accelerate** at the same rate ([for complicated reasons](https://youtu.be/wrwgIjBUYVc?feature=shared)), so therefore the objects with more **mass** will also have more **force** when they hit the ground
Mass, and therefore the energy from a fall, is proportional to volume, while the strength is only proportional to area. If you double the diameter and keep the same speed, the impact energy gets multiplied by 8, where cross sectional area only gets multiplied by 4. (square cube law)
It also has to do with the way micro-defects propagate. In a brittle material, unavoidable defects and gaps, invisible to the naked eye, are omni-present. And once they start propagating due to stress, it’s non-reversible. A bigger piece of glass is just statistically way WAY more likely to have a weak point than a small piece. It’s the same reason why you can have a large ceramic or glass slab/plate and shatter it easier with less force compared to smaller pieces.
ELI5: Bigger things have more tiny invisible cracks compared to smaller things, and that makes it break easier.
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