Understanding Heat Transfer in a Red Hot Wire Immersed in Water: An Analysis

AI Thread Summary
The discussion centers on the heat transfer mechanisms when a red hot wire is immersed in water, particularly regarding the movement of small particles on the water's surface. The initial assumption of kinetic theory is challenged, as the participant questions whether conduction applies in this scenario, given the rapid movement of both water molecules and particles. It is clarified that conduction occurs between any two masses in contact, regardless of their state of matter or motion. The conversation also touches on the potential for calculating the kinetic energy increase of water molecules upon contact with the wire and the relevance of Brownian motion for larger particles like glitter. Overall, the principles of heat transfer, including conduction and convection, are emphasized as applicable across different states of matter.
jangheej
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confusing heat transfer...

hi
im really confused about the exact heat transfer mechanism of the phenomenon i observed
the situations simple: if you immerse a red hot wire into water with small particles floating on the surface, the particles move really fast.

at first, i thought it could be explained simply by the kinetic theory of matter.
the kinetic energy of particles increase and they move fast.

1. but, after thinking more deeply about I am not so sure how exactly the heat is transferred.
conduction doesn't seem like it since conduction applies to "solids" or "stationary liquid".
but in this case, the water molecules move very fast as well.
so, if that's the case, it seems like a "bulk motion", so does that mean this is a case of convection?

2. also, thinking about the very moment that the water molecule hits the wire and bounces off... by how much does the kinetic energy of the water molecule increase? is it possible to calculate?

3. i used the glitter as the particles in my experiment, which is relatively large.
so, can i still think of it as brownian motion? can i think of the particles suspended in the liquid and therefore in thermal equilibrium with the water molecules??

help me please! :0
 
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Where did you get the idea that conduction only applies to solids and stationary liquids? Put any two masses into physical contact. If the two masses have different temperatures, then conduction will occur. The net heat transfer will be from the hotter to the cooler. This applies to all phases of matter: solids, liquids, gases, and plasmas. It occurs if the matter is stationary or if it is in motion.

As a practical consequence of this principle, most of the heat conducted from the Earth to its atmosphere is from a moving liquid (the world ocean) to the moving air immediately above it.
 
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