A fin of length l protrudes from a surface held at temperature T0; it being higher than the ambient temperature Ta. The heat dissipation from the free end of the fin is stated to be negligibly small. What is the temperature gradient \((\frac {dT}{dx})_{x=L}\) at the tip of the fin?

A fin of length l protrudes from a surface held at temperature T0; it

1.	A fin of length l protrudes from a surface held at temperature T0; it being higher than the ambient temperature Ta. The heat dissipation from the free end of the fin is stated to be negligibly small. What is the temperature gradient \((\frac {dT}{dx})_{x=L}\) at the tip of the fin?
A.	Zero
B.	\(\frac {T_0 -T_l}{l}\)
C.	h(T0 - Ta)
D.	\(\frac {T_l -T_a}{T_0 -T_a}\)
Answer» B. \(\frac {T_0 -T_l}{l}\)

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A fin of length l protrudes from a surface held at temperature T0; it being higher than the ambient temperature Ta. The heat dissipation from the free end of the fin is stated to be negligibly small. What is the temperature gradient \((\frac {dT}{dx})_{x=L}\) at the tip of the fin?

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