Let us now take a closer look at the tip of a growing dendrite. The situation is different from that of a planar interface because heat can be conducted away from the tip in three dimensions. As a result of the Gibbs-Thomson effect equilibrium across a curved interface occurs at an undercooling Tr below Tm given by______ (Latent heat of fusion per unit volume)

Let us now take a closer look at the tip of a growing dendrite. The si

1.	Let us now take a closer look at the tip of a growing dendrite. The situation is different from that of a planar interface because heat can be conducted away from the tip in three dimensions. As a result of the Gibbs-Thomson effect equilibrium across a curved interface occurs at an undercooling Tr below Tm given by______ (Latent heat of fusion per unit volume)
A.	Tr = 2 Tm/(L*r)
B.	Tr = 2Tm/(L*r)
C.	Tr = 2Tm/(L* *r)
D.	Tr = 2 Tm/L
Answer» B. Tr = 2Tm/(L*r)

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