# An iPhone falling on carpet is fine, is it true? [closed]

I heard that an iphone falling on carpet would not cause damage to it, both internal and external.

Any physical explanation for this?

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## closed as off topic by Frédéric Grosshans, Raskolnikov, j.c., Noldorin, nibotDec 3 '10 at 1:18

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I'd bet a lot of money that I could find a height from which falling onto a carpet would damage an iPhone! – ptomato Dec 2 '10 at 7:50
@ptomato, why you say so? Is it because the carpet is elastic and can absorb crash? – Graviton Dec 2 '10 at 7:57
Vote for close as "too trivial". One could answer "because the carpet is soft". Might be OK with a different formulation, explaining why the "because the carpet is soft" answer is not OK, not enough. – Frédéric Grosshans Dec 2 '10 at 10:31
This isn't real physics I'm afraid. Popular science, at best... – Noldorin Dec 2 '10 at 19:17

During a fall, the phone's potential energy ($mgh$) is converted into kinetic energy ($\frac{1}{2}mv^2$). When the phone hits the floor, it stops falling, so the kinetic energy becomes zero. That energy has to go somewhere. Some of it will be used to exert a force on the phone. If the floor is hard, then the phone gets that energy at the moment of impact, and that will probably be enough to break it. If the floor is a carpet, which is compressible, then the phone will compress it and the energy will be stored as potential energy in the "springiness" of the carpet, and released gradually.
If you drop the phone from high enough, say the top of a crane, onto a carpet, then it will still break. That's because there was more potential energy to start with, because $h$ was 100 meters instead of 1. If the phone hits the carpet and compresses it as much as possible, but still has enough kinetic energy left to break on impact, then it certainly will break.