Grade 12 Physics: Tension Formulas & Static Equilibrium

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The discussion focuses on challenges faced by a Grade 12 student with tension questions and static equilibrium in physics. Key formulas for static equilibrium include net force in the y-direction and x-direction being zero, along with net torque also equaling zero. A specific example involving two boxes connected by a string on different surfaces is provided to illustrate tension calculations. The student expresses uncertainty about the calculations and seeks confirmation on the math involved in determining the tension and the time it takes for the boxes to slide. The conversation highlights the need for additional practice problems and clarification on tension concepts in physics.
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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?
 
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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 don't 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?
 
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
 
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 that's right idk check my math. Does your book have the answer in the back to check it?
 
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