For laminar forced convection over a flat plate, if the

For laminar forced convection over a flat plate, if the free stream velocity increases by a factor of 2, the average heat transfer coefficient

1. remains same
2. decreases by a factor of √2
3. rises by a factor of √2.
4. rises by a factor of 4

For laminar flow, Nu = 0.664 (R_e)^0.5 (P_r)^0.33

	hL	= 0.664		ρVD		^0.5	(P_r)^0.23
	k			μ

h ∝ V^0.5; h ∝ √V
So when free stream velocity increases by a fact or of 2, t hen t he aver age heat transfer coefficient rises by a factor of √2.