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1 vote
0 answers
79 views

Using the trapezoidal rule for the Maxwell-Boltzman function

Background I approached my physics professor with question 1 from this LibreTexts resource. (at the bottom of the page), to better understand the material via self-study. Question Using the Maxwell-...
Jessie's user avatar
  • 1,426
0 votes
0 answers
70 views

Arc length vs Surface of revolution.

I don't understand why these two problems are solved differently here the first one $fig(1)$ and 2nd one $fig(2)$. Why did we take the limit $\displaystyle \lim_{r\to0^+}\int_r^\pi \sqrt{2-2cost}\...
user avatar
0 votes
1 answer
63 views

Why can we apply the surface area of revolution theorem to a spiral?

To find the surface area generated by revolving function f which is smooth on the interval [a,b] and $f(y) \ge0$ around the y-axis we can use the formula $$S=\int_a^b 2\pi rdl =\int_a^b 2\pi f(y)\...
Youssef Mohamed's user avatar
1 vote
2 answers
538 views

When can I apply the trapezoidal rule?

An artificial lake has the shape illustrated below , with adjacent measurements 20 feet apart. Use suitable numerical method to estimate the surface area of the lake. I know how to solve this problem ...
Youssef Mohamed's user avatar
4 votes
1 answer
387 views

I've never been so confused (Application of Integral Calculus)

Here's a problem on Application of Integral calculus to find the work done in moving a particle. I was able to 'reach' the 'right answer'. But I'm totally confused and utterly dissatisfied with the ...
Abhishek A Udupa's user avatar
1 vote
1 answer
90 views

Why $\int_0^h 2 \pi \frac{rx}{h} \, dx \neq \pi rl$

I'm new to calculus. I saw a proof for volume of cone using integral. They taken the cone's vertex at $(0,0,0)$, it's base centre at $(h,0,0)$ and it's radius is $r$ $$V=\int_0^h \pi \left(\frac{rx}{h}...
Sunil kumar's user avatar
3 votes
5 answers
110 views

Finding the area bounded by $y = 2 {x} - {x}^2 $ and straight line $ y = - {x}$

$$ y =\ 2\ {x} - {x}^2 $$ $$ y =\ -{x} $$ According to me , the area $$ \int_{0}^{2}{2x\ -\ { x} ^2}\, dx \ + \int_{2}^{3}{\ {x} ^2\ -\ 2{x} }\, dx \\ $$ Which gives the area $ \frac{8}{3}$ But ...
user avatar
0 votes
1 answer
4k views

UNRESOLVED: Pushing oil out of a tank using work integration

I have a tank of oil with a density of $900\frac{kg}{m^3}$. My tank has a spout that is $2$ meters tall and the general radius of the tank is $6$ meters. It is half full of oil and I want to find the ...
Computer's user avatar
  • 575
0 votes
1 answer
2k views

How can I write the radius equation for the disk method if the axis of revolution intersects the area between the curves

A specific example would be revolving the area between $x^2-5$ and $5x$ below the $x$-axis about $y=-2$ PS - in general, I am assuming that revolving about any other horizontal or vertical line ...
Joe Stavitsky's user avatar
6 votes
1 answer
2k views

Volume vs. Surface Area Integrals

In order to find the volume of a sphere radiud $R$, one way is to slice it up into a stack of thin, concentric disks, perpendicular to the $z$-axis. a disk at any point $z$ will have radius $r=\sqrt{R^...
Dylan's user avatar
  • 16.6k
3 votes
2 answers
5k views

Interpretation of definite integrals [closed]

It is known from the Fundamental Theorem of Calculus that $$\int_a^b f(x)=F(b)-F(a).$$ This has the geometric interpretation of the net area between $f(x)$ and the $x-$axis. I suspect that there are ...
Daryl's user avatar
  • 5,616