Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

ChrisV Group Title

-16t^2+vt+s A ball is thrown straight down from the top of a 220-foot building with a velocity of -22feet per second. What is its velocity after falling 108 ft?

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. cyter Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\huge v_{f}^2 = v_{i}^2+2ad\] d=108ft a=-9.8m/sec^2 vi=-22ft/sec

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

    s(t)=-16t^2-22t+220 This function measures how far above the ground the ball is, so when it falls 108 ft, it is 112 ft above the ground s(t)=-16t^2-22t+220=112 s(t)=-16t^2-22t+108=0 Using quadratic equation to solve for t: \[t=\frac{22 \pm \sqrt{484-4(-16)(108)}}{2(-16)}=\frac{22 \pm 86}{-16}\] We can discard the 22+86 since it will yield a negative time. So t=(22-86)/-32=2 v(t)=s'(t)=-32t-22 v(2)=-32(2)-22=-64-22= -86ft/s

    • 2 years ago
    • Attachments:

See more questions >>>

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...


  • 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.