How Do You Calculate the Volume of Solid B Bounded by Given Surfaces?

Click For Summary
The discussion focuses on calculating the volume of solid B, which is defined by the surfaces x^2 + y^2 = 1 and x^2 + y^2 + z^2 = 2^2. The user seeks confirmation on the integration setup, specifically the function and limits used in cylindrical coordinates. They initially derived a volume of Pi*sqrt(3), but this does not align with the expected volume calculated using the cylinder volume formula, yielding Pi*2*sqrt(3). The discrepancy highlights the importance of correctly applying integration techniques and understanding geometric interpretations. Clarifying these calculations is essential for accurate volume determination.
Chibus
Messages
5
Reaction score
0

Homework Statement


Sketch the solid B that lies inside the surface x^2 + y^2 = 1 and is bounded above and below by the surface x^2 + y^2 + z^2= 2^2. Then find the volume of B.


Homework Equations



projxy = projection onto the xy plane, proj zy = projection on the zy plane

The Attempt at a Solution


(See attached)

http://img511.imageshack.us/img511/440/chibusq.jpg

I just wanted to check whether my definition of the integration is correct, meaning:

1) Is the function of the integration right? (Since the circle on the xy plane is x^2 + y^2 = 1, I've used that)

2) Are the limits correct?

Thanks for any help!
 
Last edited by a moderator:
Physics news on Phys.org
Any help?

I've converted the above integral into cylindrical coordinates and solved it, and I ended up with Pi*sqrt(3) as the solution. However, it doesn't match the answer of solving the cylinder by using the formula V(cyl)=pi*r^2*h = pi*(1)^2*2*sqrt(3) = pi*2*sqrt(3)
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

Similar threads

  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 27 ·
Replies
27
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K