The force (f) of the wind on a flat surface positioned at a right angle to the direction of the wind varies jointly with the area A of the surface and the square of the speed of (v) of the wind. A wind of 40mph blowing on a window measuring 3 feet by 4 feet has a force of 160lbs. what is the force on the window measuring 4 feet by 5 feet caused by a wind of 90mph?

Question

jpes2193 · Answer

I understand the F=kxy the areas are 12 feet for the first windown and 20 feet for the second window. other than that im clueless on where to start with this problem.

jpes2193 · Answer

@ribhu

ribhu · Answer

F= k (xy)(v)^2
160=k(12)(160)
k=1/12

ribhu · Answer

now new case
F = 1/120(20)(8100)
F=8100/6 = 1350 lbs

jpes2193 · Answer

what is k related to ?

ribhu · Answer

i think this should be the case. k is any thing which will homogenise this equation

ribhu · Answer

knowing k is not our concern here

jpes2193 · Answer

okay so my teacher never taught us this... can you explain that differently ? and 1350 is one of the answers

ribhu · Answer

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