Convection is transfer of heat between a solid and a moving fluid. Boiling or condensing processes are example for convection processes.
The formula for convection is:
<span>q = hc A dT</span>
where
<span>hc is convective heat transfer coefficient of the process (W/(m2K) or W/(m2oC <span>q
</span>A<span> is the heat transfer area of the surface (m2, ft2)
</span><span>hc </span><span>= convective heat transfer coefficient of the process (W/(m2K) or W/(m2oC), <span>Btu/(ft2 h oF)</span>)</span><span>q is heat transferred per unit time (W, Btu/hr)</span>dT is the <span>temperature difference between the surface and the bulk fluid (K or oC, F)</span>
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<span>There is no special name for that. Physics is usually just concerned with "forces", and doesn't specify whether the force pushes or pulls. If you want to be more specific, you can just call it a "pulling force".
I hoped this was satisfying!:)</span>
When you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. This increases the space in your chest cavity, into which your lungs expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.
Answer:
Explanation:
The resistance of a wire is given by:
where
is the resistivity of the material
L is the length of the wire
A is the cross-sectional area of the wire
1) The first wire has length L and cross-sectional area A. So, its resistance is:
2) The second wire has length twice the first one: 2L, and same thickness, A. So its resistance is
3) The third wire has length L (as the first one), but twice cross sectional area, 2A. So, its resistance is
By comparing the three expressions, we find
So, this is the ranking of the wire from most current (least resistance) to least current (most resistance).
