Question

A horizontal board of negligible thickness and area 1.0 m2 hangs from a spring scale that reads 50 N when a 4.0 m/s wind moves above the board. The air below the board is stationary. What does the scale read when the wind stops? The density of air is 1.25 kg/m3 .

Answer 1

Scale reading for no wind
Step-by-step explanation:
From the question we are told that
Area
Weight of board
Velocity
Density of air
Generally the equation for pressure difference by Bernoulli equation is mathematically given by


Generally force acting on the board by air is mathematically given by


Therefore
Scale reading for no wind W'


Scale reading for no wind W'=60Ng