# Volume of Spheroid

• Jan 25th 2013, 02:02 AM
aqualibra86
Volume of Spheroid
Find the volume of the spheroid formed by the revolution of the area bounded by the ellipse x^2/(a^2)+ y^2/(b^2)=1 about the major axis a.

Kindly Help!

• Jan 25th 2013, 02:37 AM
earboth
Re: Volume of Spheroid
Quote:

Originally Posted by aqualibra86
Find the volume of the spheroid formed by the revolution of the area bounded by the ellipse x^2/(a^2)+ y^2/(b^2)=1 about the major axis a.

Kindly Help!

1. The axis a is placed on the x-axis.
A rotation volume with the x-axis as axis of rotation is calculated by: $\displaystyle V_{rotx} = \int (\pi \cdot y^2)dx$

2. Since you need y² solve the equation of the ellips for y² and use the formula from #1. The bounds of the integral are -a and a. (Why?)
• Jan 25th 2013, 02:58 AM
aqualibra86
Re: Volume of Spheroid
I have did in this way and get V=4/3 (pi) a b^2, just need to know that if this is correct answer .. ?
• Jan 25th 2013, 06:46 AM
earboth
Re: Volume of Spheroid
Quote:

Originally Posted by aqualibra86
I have did in this way and get V=4/3 (pi) a b^2, just need to know that if this is correct answer .. ?

Correct! (Clapping)
• Jan 25th 2013, 07:03 AM
aqualibra86
Re: Volume of Spheroid
Thanks alot!