Attraction of water droplet to my finger?

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Water droplets can jump to a dry finger due to the attraction between the negatively charged oxygen end of water molecules and the positively induced charge on the finger. This phenomenon is primarily explained by adhesion, where the water molecules are drawn to the finger. If the finger is slightly wet, the effect is enhanced by hydrogen bonding and the presence of ionic compounds in sweat, contributing to both cohesion and adhesion. The interaction is a result of induced dipole interactions, confirming the role of molecular polarity. Overall, the jumping droplets illustrate the principles of molecular attraction and surface tension.
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After a rain, when there are tiny water droplets hanging down from places, I can put my dry finger near one of the droplets and if my finger is close enough to the droplet, it will jump onto my finger. Just like a metal jumping onto a magnet.

What physical explanation could be given here? Is it simply the negative ends of all the water molecules in the droplet attracted to my positively induced finger?
 
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i think you hit it, negative polarity on the oxygen end of water attracts to your positively charged finger.

if you're finger was slightly wet though it would have been due partly to the polarity of the molecules and partly due to hydrogen bonding
 
rctrackstar2007 said:
i think you hit it, negative polarity on the oxygen end of water attracts to your positively charged finger.

if you're finger was slightly wet though it would have been due partly to the polarity of the molecules and partly due to hydrogen bonding

This is indeed a good point, sweat contains not only the polar H2O water molecule, but also ionic compounds, which could contribute to the effect. If your finger is damp / sweaty you will have both cohesion and adhesion.

~H
 
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