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Homework Help: Tension Formulas

  1. Jan 1, 2005 #1
    I am in grade 12 doing level 3 Physics.


    For some reason i keep getting stuck on tension questions and static equilibriums

    Would anyone know the formulas for these (as my book really does not seem to be helping me) and where i can find some practice questions on the subject?
     
  2. jcsd
  3. Jan 1, 2005 #2
    I am doing that stuff right now too.

    Static Equilibriums is real easy for me, the equations are that Net force in y direction = 0 net force in x direction = 0 and net torque = 0 using those forumlas along with provided information for the problem should be enough to solve it. Unless there is something more comples your working with becasue I dont know what is meant by level 3 physics?

    Im not exactly sure what you mean by tension questions? like just rope tension? do you have a sample problem?
     
  4. Jan 1, 2005 #3
    Well, the reason i would be having trouble with statics is that i pretty much missed that entire section due to sickness..

    But as for tension, i do have an example:


    two boxes, each of mass 40 kg, are tied together. Box 2 is on a surface angled 60 degrees below the horizontal level of the flat surface that box 1 is on. If both surfaces provide a frictional coefficient of 0.15;

    a) What is the tension in the string
    b) Starting from rest, how long does it take the system of boxes to slide 1.50m
     
  5. Jan 1, 2005 #4
    Ok so the box on the flat surface has a force of 58.8 N holding it in place (40)9.8(.15)

    The box on the sloped surface has a force of 145.077 N pulling it down the slope(40)9.8(cos(60))-(40)9.8(sin(60))(.15)

    So I think that you add the two or subtract, I think its add because they are in opposite directions so it would be 203.877 N? sig digs. I tihnk thats right idk check my math. Does your book have the answer in the back to check it?
     
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