Vertical pressure on soft drink can

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The discussion focuses on calculating the net inward force on the vertical sides of a soft drink can when internal pressure is reduced to zero. The can's dimensions are provided, and atmospheric pressure is noted as 1 atm or 101325 Nm-2. The initial calculations incorrectly assumed equal pressure on the top and sides, leading to confusion. It is clarified that the net force on the vertical sides ultimately results in zero when considering the direction of forces. The conversation highlights the importance of correctly interpreting the problem and converting measurements accurately.
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Homework Statement


In a classroom demonstration, the pressure inside a soft drink can is suddenly reduced to essentially zero. Assuming the can to be a cylinder with a height of 13cm and a diameter of 6.5cm , find the net inward force exerted on the vertical sides of the can due to atmospheric pressure.

Homework Equations


Pressure= force/area
area of a cylinder is 2πrh +2πr2
force due to gravity is mg

The Attempt at a Solution


I know that because there is no pressure inside the can to counteract the air pushing inward, the can collapses but I am not sure how to calculate the force on the vertical sides of the can. Atmospheric pressure is 1 atm at sea level which is 101325 Nm-2. If the pressure on the top of the can is the same as that of the sides than you multiply the pressure by area to get force which gives 6991425 but this is incorrect probably because the pressure on the top isn't the same as the pressure on the sides but I don't know what the formula for it is.
 
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reshald said:
net inward force exerted on the vertical sides of the can
What's the area of the cylindrical surface of the can?
 
Thank you that fixed it. Also I didn't convert the diameter into meters. Thank you.
 
Actually, this is a very poorly worded question. The net force by the air on the vertical sides of the can has to take into account the direction of the forces, and this results in a net force of zero.

Chet
 
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