Community RSS Feed https://community.wolfram.com RSS Feed for Wolfram Community showing any discussions in tag Wolfram|Alpha sorted by active Unexpected integration result in Wolfram|Alpha? https://community.wolfram.com/groups/-/m/t/2374008 Hello All, I&#039;m working on a problem which I&#039;m currently stuck on. I would like to calculate the volume of fluid in a horizontal end cap. ![Impression of shape horizontal tank end cap] (here k =1 and r = 1.5) What i do is: Get the describing equation. ![Equation of curve] Then rotate it along the x axis. This gives a circle over the x axis on any given point on the curve. And finally integrate over the y axis. To get the volume. ![Equation of integration] Unfortunately if I put in numbers for k and r and try to compute the volume with y i don&#039;t get the correct results. A full volume with k =1 and r=1.5 should give me: 22.88. What have I done wrong? : https://community.wolfram.com//c/portal/getImageAttachment?filename=MImpressionhorizontaltankendcap.png&amp;userId=2373861 : https://community.wolfram.com//c/portal/getImageAttachment?filename=Curveequation.png&amp;userId=2373861 : https://community.wolfram.com//c/portal/getImageAttachment?filename=Integrationpicture.png&amp;userId=2373861 Wytse Haanstra 2021-09-26T11:49:57Z