1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I need help guys please

  1. Nov 21, 2008 #1
    Hello guys,

    I do not know how to solve these problems could you help me please?

    1- A satellite of mass 59.0 Kg is being pulled out of orbit by 450.0 Netwons of gravity. Small thrusters are used to maneuver the satellite back to its orbite. What thrust would cause the satellite to move with a constant velocity?

    2- A US Army rope has a tensile strength of 5000.0 Netwons- this is the greatest force you may exert on it without breaking. Suppose this rope is used by a soldier rappelling down a building or cliff.
    a) What is the maxiumum deceleration of a 50.0 kg rappeller that the rope can withstand?
  2. jcsd
  3. Nov 21, 2008 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Welcome to PF.

    You'll need to show an attempt at solving the problems before receiving help. It's the policy here. In other words, those items that you deleted when you posted need to be addressed.
  4. Nov 21, 2008 #3
    Is that answer correct?

    Force=mass*acceleration so


    acceleration = 5000/50 = 100 m/s^2
  5. Nov 21, 2008 #4


    User Avatar
    Staff Emeritus
    Science Advisor

    Which problem is that supposed to be the answer to?
  6. Nov 21, 2008 #5
    I think for Q2 that the pushing and pulling forces should be equal and the accerleration is zero.


    T=450 T is force
  7. Nov 21, 2008 #6
    Hello HallsofIvy,
    is my answer right or I need to count the Earth's gravity?
  8. Nov 21, 2008 #7


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    That's correct for question #1. Just remember to include units.

    450.0 N is the force of the Earth's gravity, so you have already counted it.
  9. Nov 21, 2008 #8
    Thanks Redbelly98, HallsofIvy I apperciate your responsoes
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: I need help guys please
  1. I need help please? (Replies: 1)