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RETIREDFAN1

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🌬️ How much force is exerted to a flag. pole with a flag in windy conditions? 🌬️

#sondreaas #education #Constitution #knowledge #physics

🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴 Since 17th of May is Norway's constitution day I though it would be funny to calculate how much force that is being exerted to a flagpole when the wind blows, so let’s do some calculations🎉 📐🔍

Let’s take the following scenario:

- Dimension of flag: 2m wide and 1 meter high.
- The wind speed is: 10 m/s
- The flagpole height: 12 meters
- Flag mounted at 11 meters height
- Diameter of the Flagpoler: 0.1 meters
- Drag coefficient for the flag: 1.2
- Air density: 1.225 kg/m³
🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴🇳🇴
Calculations

1. Wind Force on the Flag:
Fw = 0,5 * 1,225 * (10m/s)^2*1,2 * (2*1) = 147nm
1,225 is the density of the air� 10m/s is the velocity of the wind� 1,2 is the «drag coefficient for the flag
(2*1) is the flag itself�
2. Moment on the Flagpole due to the Flag:
M flag = 146* (11+0,5) = 147 * 11,5 = 1690,5 nm

3. Wind Force per Unit Length on the Flagpole:
fp = 1/2*1,225*(10)^2 *1,2*0,1 = 7,35 nm

4. Bending moment on the flagpole due to distributed load:
M pole= 7,35*x*dx* x^2/2= 7,35*72 = 529.2nm� (The formula is confusing because i am not able to write the integral sign and the limit)�
5. Total Bending Moment at the Base:
Mb = 1690.5 + 529.2 = 2219.7 nm

These calculations show the total bending moment at the BASE of the flagpole due to the wind force on the flag and the flagpole.
This was a smal flag, imagine how much force it would be if the flag was much bigger, the flagpole was higher- and it was both windy and raining, the forces would have been much higher.

I wish all a happy constitutional day! 

Best wishes Sondre Åkerøy Sundrønning
Physicist 🇳🇴🇳🇴

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The Chinese satellite "Longjiang-2" took a picture that shows the far side of the Moon, and behind it our beautiful planet, carrying life in the immense cosmic void.

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This is K2-18b, a potentially habitable planet covered with oceans and about 2.6 times the size of Earth. 
JWST has just detected carbon dioxide and methane in its atmosphere which can only be produced by living beings.

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