Quantcast

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

gifty91 Group Title

Superman dangles his watch from a thin piece of string while he is taking off from the ground horizontally at a constant acceleration a. He notices that the string makes an angle (theta) with respect to the vertical. After 20 seconds, his speed is v=134 m/s. Estimate the angle (theta).

  • 2 years ago
  • 2 years ago

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

    Use the time and final velocity to find the horizontal acceleration. Use Newton's 2nd Law and do a vector triangle with forces. The vertical force is mg, the horizontal force is ma (the force superman needs to exert on the watch to give it a horizontal acceleration of 'a'). \[\tan \theta = \frac{ mg }{ ma }\] and the unknown mass of the watch cancels.

    • 2 years ago
  2. gifty91 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    I got 6.7 m/s^2 for the horizontal acceleration, and for theta I got 55.6 degrees but apparently that's wrong. I calculated the acceleration as final velocity-initial velocity/time, so the acceleration, I'm assuming should be correct. Not sure what I did wrong after that.

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

    they can understand every problem they need to go through treatment to

    • 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...

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.