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Gravity
Note: I mislabeled an earlier blog of mine "Gravity". I will try to rename it whenever I have time.
Water is a pretty heavy substance. With enough volume and enough force, water is almost unstoppable.
To lift water against the force of gravity tales some kind of energy. If you put a dry roll of toilet paper in about ½" of water (that's about 12.7mm if you swing like that)
The water will climb up into the toilet paper roll until the whole roll is soaked.
The question is: Whence came the energy that enabled the water to go upward into the roll?
Comments
Gravity...
Gravity...
that's a heavy subject.
Kris
{I leave a trail of Kudos as I browse the site. Be careful where you step!}
Probably...
Chemical potential energy, ultimately based on electric potential energy of an attractive electric force.
I don't know whether it's related to hydrogen bonding. In the water molecule, the hydrogen's electron is pulled toward the oxygen atom. That leaves the not-quite-bare proton free to glom onto a neighboring atom. I don't know if it's related to this.
This is not my immediate field of expertise.
-- Daphne Xu
Capillary action
It is due to capillary action, as described in this wikipedia entry:
https://en.wikipedia.org/wiki/Capillary_action
Deen
Thermodynamics
All real world processes are governed by the Gibbs Free Energy equation.
ΔG = ΔH - TΔS Where H is an energy term, T is the absolute temperature, and S is an entropy term.
Natural processes exhibit a negative ΔG. Either giving up energy or increasing entropy can yield that negative ΔG. Heat as a process driver works because of TΔS' impact.
G/R
A wonderful paradox
I love these kind of paradoxes.
In order to understand what's happening in the kind of simplistic language that I can follow, we need to think of different things which follow the same basic rules of physics:
1 If we imagine, instead of water, a steel ball laying on a table. Slowly roll it over the edge of the table and it falls, rapidly accelerating downwards. Where does the energy come from to accelerate the ball? We call it potential energy - energy which is stored because of an item's position - the table is higher than the floor.
2 Now instead of pushing the ball off the table, imagine sliding a permanent magnet over the top of it and the ball leaps upwards to cling to the magnet. This is no longer about gravity, but about magnetic attraction, and again, it is the position of the ball with respect to the magnet which causes it to accelerate upwards. So again, this is the stored potential energy causing the ball to move.
3 Finally, we come back to the toilet roll (and who can afford to use toilet rolls nowadays for these kinds of experiments?). Capillary action is less widely understood by the general public than gravity or magnetism, but it is the same principle. Water is attracted to many products, and we can see how, in a glass of water, it creeps slightly up the sides of the glass. But water really loves toilet rolls and it is pulled upwards by the capillary force. Again, it is the potential energy due to the dry toilet roll attracting the water towards it. Once the toilet roll is saturated, the water movement stops, and you would have to apply force (such as squeezing the water out) to make the water travel outside the roll and back down into the tray.
In each case, the energy is said to be stored as potential energy, due to its position with respect to other things which are attracting the object - the earth producing gravity, the magnet producing magnetic attraction and the toilet roll producing capillary attraction.
Hope that was slightly clearer than mud!
best wishes
Charlotte