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# Mechanics question AS level help please watch

1. I am trying to find "a" in a question and I have gotten as far as:

T1 = [mg - (√3 x ma)]/2
T2 = (2mg x T1)/√3

I was told by a teacher to sub in 0 for T1 and T2 to get 2 answers for "a", but because I don't know "m" I don't know how that helps?

Any help of where to go next would be appreiciated, thanks! Let me know if you need any more information about the question to help.
2. Whats the question? Can u post a picture?
3. (Original post by Shaanv)
Whats the question? Can u post a picture?
There you go, that's the questions (I am on part b) and the work I have done so far. Thank you! <3
Attached Images

4. (Original post by ookatiebourneoo)
There you go, that's the questions (I am on part b) and the work I have done so far. Thank you! <3
I cant see the picture properly on my mobile, but i assume that u have expressions for the tension in each string.

For a string to go slack there has to be no tension in the string, so u can find the acceleration needed to make each string go slack. By solving when T=0
5. (Original post by Shaanv)
I cant see the picture properly on my mobile, but i assume that u have expressions for the tension in each string.

For a string to go slack there has to be no tension in the string, so u can find the acceleration needed to make each string go slack. By solving when T=0

Yes that's it! But how do I solve for T=0 with the equations that I provided in the original question as I don't know the mass?
6. (Original post by ookatiebourneoo)
Yes that's it! But how do I solve for T=0 with the equations that I provided in the original question as I don't know the mass?
The masses should cancel out if I’m not mistaken.

In BC, T=0.5mg-0.5am(root 3)

When T=0, 0.5mg=0.5ma(root 3).

Can u see how mass cancels out?
7. (Original post by Shaanv)
The masses should cancel out if I’m not mistaken.

In BC, T=0.5mg-0.5am(root 3)

When T=0, 0.5mg=0.5ma(root 3).

Can u see how mass cancels out?

Yes I can see that, thanks! How do I do that for the T2 equation? Do I sub in the equation for T1? I am stugglign subbing it in then cutting down the eqation to get "a=".
8. (Original post by ookatiebourneoo)
Yes I can see that, thanks! How do I do that for the T2 equation? Do I sub in the equation for T1? I am stugglign subbing it in then cutting down the eqation to get "a=".
U have resolved horizontally to get an equation relating t1 and t2 so u can substitute in ur t1 equation, then make t2 equal to zero and rearrange. U should be able to reduce it down to find the acceleration.

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Updated: October 28, 2017
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