Quantcast

A community for students. Sign up today!

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

sweett2639

  • 2 years ago

You're filling a water balloon with a spherical shape. If the water is coming in at 4 cubic inches per second, how fast is the radius changing when the volume is 200 cubic inches? (answer: 0.0241 in/sec)

  • This Question is Closed
  1. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1351471895315:dw|

  2. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    @sweett2639 do you follow?

  3. sweett2639
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[v= \frac{ 4 }{ 3 } \pi r ^{3}\]i understand that the volume of a sphere is and that\[\frac{ dv }{ dt } = 4 inches ^{3}/\sec\] but not much more than that

  4. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1351472335325:dw|

  5. sweett2639
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so you set 200 equal to v and moved the equasion around so that r is 3.628

  6. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1351472455417:dw|

  7. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Right, we know that the volume is 200 in^3 at the moment of interest, therefore we can find what the radius of the sphere is at that moment

  8. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1351472567598:dw|

  9. sweett2639
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    everytime i try to calculate r, i get the wrong number

  10. baldymcgee6
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    http://www.wolframalpha.com/input/?i=4%2F%284*pi*%283.628%29%5E2%29 just make sure you type it into the calc correctly.

  11. Not the answer you are looking for?
    Search for more explanations.

    Search OpenStudy
    • Attachments:

Ask your own question

Ask a Question
Find more explanations on OpenStudy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.