Quantcast

A community for students. Sign up today!

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

soty2013

  • one year ago

Find the rate of change of the area of a circle per second with respect to its radius r when r = 5 cm.

  • This Question is Closed
  1. soty2013
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @ParthKohli

  2. ParthKohli
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Differentiate \(\pi r^2\) with respect to \(r\).

  3. ParthKohli
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    When you find \(f'(r)\), find \(f'(5)\)

  4. soty2013
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Thanks

  5. ParthKohli
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    The answer turns out to be the circumference.

  6. BAdhi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Actually shouldn't it be like this, $$A=\pi r^2$$ Since rate of change is associated with 'time' differentiation with respect to 't'- time, $$\frac{dA}{dt}=\pi\frac{dr^2}{dt}=2\pi r\frac{dr}{dt}$$ rate of change in radius should be given

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

    • 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.