Why does ice piece sticks on hand but not wood piece?

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    hand Ice Wood
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Discussion Overview

The discussion revolves around the phenomenon of why ice sticks to a hand but not to a piece of wood. It explores the thermal properties and interactions between ice, skin, and wood, touching on concepts of heat transfer, melting, and freezing.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that heat from the hand melts a bit of ice, which then refreezes, causing the ice to stick.
  • Another participant notes that wood is generally colder and has higher heat resistance, leading to a smaller contact area and less heat transfer.
  • It is mentioned that ice can stick to wood if it thaws and then refreezes, indicating that the interaction is not entirely absent.
  • A comparison is made to a child sticking their tongue to a metal rail, with one participant emphasizing that moisture (saliva) plays a role in the sticking process.
  • Another participant elaborates that the warmth of the flesh and its good heat conduction contribute to the melting and refreezing process, while a glove's exterior acts as an insulator.

Areas of Agreement / Disagreement

Participants express varying views on the conditions under which ice sticks to different materials, with some agreeing on the role of heat transfer while others emphasize the importance of moisture. The discussion remains unresolved regarding the extent and conditions of ice sticking to wood.

Contextual Notes

There are limitations regarding assumptions about moisture levels on the skin or wood, as well as the specific thermal properties of the materials involved. The discussion does not resolve the complexities of these interactions.

Nitesh Swarnakar
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Why does ice piece sticks on hand but not wood piece?
 
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Hello Nitesh, :welcome:

Good question ! The answer is that heat from your hand easily melts a bit of ice and the cold ice re-freezes that bit.
For the transition from wood to ice:
  • the wood is generally also a bit colder
  • the heat resistance is bigger:
    • the wood doesn't deform, so the contact area is small and
    • wood is a bad conductor for heat
It is not true that ice doesn't stick to wood at all: when the ice thaws a bit and then refreezes it can become quite well attached.
 
@BvU 's answer is correct.

It reminds me of the case when a child at my front door in winter touched a metal rail with his tongue. The tongue stuck to the rail which was very painful. But the child's clothes did not stick for the reason that @BvU said.
 
Tongue sticks because it was wet. The saliva freezes and acts as a bond. If your hand is dry, it probably won't stick to the ice.
 
Khashishi said:
Tongue sticks because it was wet. The saliva freezes and acts as a bond. If your hand is dry, it probably won't stick to the ice.

That's part of what @BvU said in #2, but not the whole story. Ice on the cold object supplies the water. It is heat from the touching object that can melt some of that ice, only to have it refreeze a moment later that causes the problem. Flesh is warm and is a good heat conductor. The exterior surface of a glove is cold and a good insulator.
.
 

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