Pressure & Force in a Beaker: Solutions

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To calculate the downward force on the bottom of a beaker filled with water, the pressure formula p = po + d*g*h was applied, resulting in a pressure of 104,730 Pa. The force was then calculated using F = p*A, yielding approximately 205.636 N. The discrepancy with the answer sheet, which states 210 N, is likely due to rounding to two significant figures. It's noted that the net force calculation should focus on d*g*h alone. Proper rounding practices should be followed, and forum rules discourage unnecessary bumps.
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Homework Statement




A 35 cm tall , 5 cm diamater cyldrical beaker is filled to its brim with water. whatis the donward force on the bottom of the beaker?

Homework Equations



p= po+ d*g*h
F= p*A
density of water is 1000

The Attempt at a Solution



p= 1.013*10^5 + 1000*9.8*0.35
p = 104,730 Pa

F= 104730 Pa * pi(0.025)^2 = 205.636 N

Answer sheet says 210 Newtons, and there are two sig digs in the question given. Either I did it wrong or I am supposed to round up. Let me know what is wrong please!
 
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Bump, anyone?
 
Nellen2222 said:
Answer sheet says 210 Newtons, and there are two sig digs in the question given. Either I did it wrong or I am supposed to round up. Let me know what is wrong please!
Looks OK to me. Round it up to two significant figures.

(And don't be bumping after just 30 minutes!)
 
Bumping is against the forum rules.

It's due to roundoff. The net force on the bottom is onlly d*g*h.
 
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