sorry guys. i had added annotations to explain that the tank's dimensions are in ft, and that everything should be in lbs and ft. nevertheless, i'll try to recreate the video in the future. :)
This is correct but you made the calculus more difficult than it had to be. Hydro Force = integral from 0 to 3 of [density*gravity*width*x*dx]. Also, units of Force is Pound-force not lb. Might confuse some people with the gravity constant in english units. So... F= 62.5*1*2*(3^2)/2 = 562.5 pound-force
Liked the video! For part 3, you might want to double-check your expression for the depth. You said the depth of the typical slice is 3-xi. This would actually be the distance from the bottom of the tank, since you defined the origin at the top. The distance from the top is the depth, so it's just X. Of course this doesn't change the value of the integral, but its important for understanding the problem. Anyways, thank for uploading!
Hello, I was wondering why it's (3-xi), not (xi)? I had one problem similar to this except it's submerged 1ft below the water, so --> F (x=1->4) = Integral of 62.5 * 2x dx
If the pressure is in lbs/ft^2 and the area is in metres^2, the answer is not just confusing, it's wrong. Can you upload this again, but corrected to either Imperial or metric units. Formulas only work if the same system of units is used throughout. The metric system (S.I.) uses metres, kilograms and seconds (mks) as the base for other units. A metre squared is equivalent to 10.764 square feet so the answer is wrong by a factor of over 10. Students beware. Also see comment from Nome Munt, below.
THIS IS INCORRECT. the depth is just x... not 3-x. i spent about an hour trying to figure out why its 3-x, but it is incorrect. part 1 and 2 are right... just double check part 3. good explanation for the other parts of the problem though. your videos are quite helpful!
It works either way. In your way with just x, it's 125*(4.5). With 3-x, it's 125*(9-4.5), which is the same answer. It is just working backwards really.
317andrew317 oh yes, youre correct, youll get the same answers, but the way she did it make absolutely no intuitive sense to me. i think of force as the force everything above that ith rectangle pushing down on it, and if you think that way, then the depth of that rectangle is x. i don't really see how 3-x makes intuitive sense in these problems (maybe it does to some people, and if it does, i'd love to hear your explanation).
Yeah I know what you mean. I am just doing my hydrostatic forces homework right now and looking ahead I see all sorts of non-rectangular shapes. I am assuming she did it that way to prepare us for other shapes such as a trapezoid. With a trapezoid you cant work backwards/forwards like here where it was 9 - 4.5 or just 4.5. Since the bottom and top will be different you have to work one way. A rectangle you can flip and it'll be the same if you flip a triangle or trapezoid the pressure would change. This is from what I am gathering.
317andrew317 you will never be required to take the depth the way she did. in my calc B class, i ALWAYS took the depth as the distance from the top of the slice to the top of the water.
sorry guys. i had added annotations to explain that the tank's dimensions are in ft, and that everything should be in lbs and ft. nevertheless, i'll try to recreate the video in the future. :)
You're a princess! Thank you for making the world a better place to live in!
Bless you, good human. This was ancient greek to me 10 minutes ago.
lol...glad I could help! :)
You might want to go ahead and check your unit conversions. Feet and Meters are not interchangeable.
Thanks!
This is correct but you made the calculus more difficult than it had to be. Hydro Force = integral from 0 to 3 of [density*gravity*width*x*dx]. Also, units of Force is Pound-force not lb. Might confuse some people with the gravity constant in english units. So... F= 62.5*1*2*(3^2)/2 = 562.5 pound-force
Liked the video! For part 3, you might want to double-check your expression for the depth. You said the depth of the typical slice is 3-xi. This would actually be the distance from the bottom of the tank, since you defined the origin at the top. The distance from the top is the depth, so it's just X. Of course this doesn't change the value of the integral, but its important for understanding the problem. Anyways, thank for uploading!
Can you please show me how to indicate cube root of 10 using the divide and average method or newton's method? Thank you
Hello, I was wondering why it's (3-xi), not (xi)? I had one problem similar to this except it's submerged 1ft below the water, so --> F (x=1->4) = Integral of 62.5 * 2x dx
Well done! Just the units confused me! Anyway thanks!
Another useful info! Thanks K!
Youre the best
i think the depth is not (3-x) instead it's suppose be x
Thank you!
Sarah Lee You're welcome!
For half filled cubic container how to find hydrostatic force,open to atmosphere
My goodness. I've never like Calc so much in my entire life, after this video.
Awww thanks! I:) 'm sorry the units were confusing!
DO YOU HAVE MIX UNITS FT AND METERS
Thank madame
You're welcome, Piseth! :)
thank you.
why do you use both meters and feet? its confusing haha
If the pressure is in lbs/ft^2 and the area is in metres^2, the answer is not just confusing, it's wrong. Can you upload this again, but corrected to either Imperial or metric units. Formulas only work if the same system of units is used throughout. The metric system (S.I.) uses metres, kilograms and seconds (mks) as the base for other units. A metre squared is equivalent to 10.764 square feet so the answer is wrong by a factor of over 10. Students beware. Also see comment from Nome Munt, below.
Hi! :)
THIS IS INCORRECT. the depth is just x... not 3-x. i spent about an hour trying to figure out why its 3-x, but it is incorrect. part 1 and 2 are right... just double check part 3. good explanation for the other parts of the problem though. your videos are quite helpful!
It works either way. In your way with just x, it's 125*(4.5). With 3-x, it's 125*(9-4.5), which is the same answer. It is just working backwards really.
317andrew317 oh yes, youre correct, youll get the same answers, but the way she did it make absolutely no intuitive sense to me. i think of force as the force everything above that ith rectangle pushing down on it, and if you think that way, then the depth of that rectangle is x. i don't really see how 3-x makes intuitive sense in these problems (maybe it does to some people, and if it does, i'd love to hear your explanation).
Yeah I know what you mean. I am just doing my hydrostatic forces homework right now and looking ahead I see all sorts of non-rectangular shapes. I am assuming she did it that way to prepare us for other shapes such as a trapezoid. With a trapezoid you cant work backwards/forwards like here where it was 9 - 4.5 or just 4.5. Since the bottom and top will be different you have to work one way. A rectangle you can flip and it'll be the same if you flip a triangle or trapezoid the pressure would change. This is from what I am gathering.
317andrew317 you will never be required to take the depth the way she did. in my calc B class, i ALWAYS took the depth as the distance from the top of the slice to the top of the water.
:D
I like your voice.
the depth is just X i beleive.
hiiii :-D
You confused me talking too much
poop!