# Which would hurt more a water bottle or a frozen water bottle?

## Main Question or Discussion Point

Ok so me and my friends are having a debate about this and I would just like to prove once and for all that the Frozen water bottle would hurt worse.
His idea is that the unfrozen one, filled all the way to the top would have more mass than a frozen one filled to the rim.

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Hurkyl
Staff Emeritus
Gold Member
Give him a choice between you throwing a large pillow at him, or you throwing a small rock. Of course, that only matters at some angles. I have a hard time imagining that the difference in mass is noticeable.

i know water isnt great at being compressed but surely the impact time of the water bottle will be longer as the bottle will deform and have a longer time in contact with your head (and so less pain), where as the ice bottle is solid and so the impact time will be shorter and therefore a greater impact. like comparing the air bag of a car (water bottle) with the steering wheel (ice bottle).

i think that makes sense...

It is obviously the frozen water bottle. Your friend (let's just call him James) is wrong.

i know water isnt great at being compressed but surely the impact time of the water bottle will be longer as the bottle will deform and have a longer time in contact with your head (and so less pain), where as the ice bottle is solid and so the impact time will be shorter and therefore a greater impact. like comparing the air bag of a car (water bottle) with the steering wheel (ice bottle).

i think that makes sense...
Yes that is correct, i was just trying to see how many people would agree with me. The other thing that my friend debated was that in a "perfect" world, the bottle wouldnt compress. (not sure exactly what he ment by perfect) So then the question would be since the bottle compressing has no more factor, would the water being heavier or the ice being solid have a greater impulse(impulse meaning time in contact with head*force)