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1. I'm on question 14 below. The answer for AM is 2.99m but I'm getting 2.96m.

What am I not doing properly, please?
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4. (Original post by maggiehodgson)
I'm on question 14 below. The answer for AM is 2.99m but I'm getting 2.96m.

What am I not doing properly, please?
I'm not sure where you have gone wrong but I would have considered .

My equation for this problem is . This leads to the solution you gave. Can you see how I obtained this?

Hope this helps but if not hang on for ghostwalker's always superior explanation.
5. (Original post by BabyMaths)
Hope this helps but if not hang on for ghostwalker's always superior explanation.

(Original post by maggiehodgson)
What am I not doing properly, please?
You assumed that the top spring would be stretched and the bottom one compressed, which in itself is not a problem - though you have to be more careful thereafter.

When working out the extension is "". If you go with that it will work out correctly.

It is far easier, as BabyMaths did and I would do, to assume both springs are stretched.
6. (Original post by BabyMaths)
I'm not sure where you have gone wrong but I would have considered .

My equation for this problem is . This leads to the solution you gave. Can you see how I obtained this?

Hope this helps but if not hang on for ghostwalker's always superior explanation.

That is so obvious now that you've told me.

Thank you.
7. (Original post by ghostwalker)

You assumed that the top spring would be stretched and the bottom one compressed, which in itself is not a problem - though you have to be more careful thereafter.

When working out the extension is "". If you go with that it will work out correctly.

It is far easier, as BabyMaths did and I would do, to assume both springs are stretched.
It all makes sense. I will remember that for future.

If I did it my way, MB compressed, I'm thinking then T2 would be Thrust not Tension so T1+T2 = 5g? I'll give that a go and see if it's true.

However, I'll redo my drawing and do it the obvious way for my notes.

Thanks.
8. (Original post by maggiehodgson)
If I did it my way, MB compressed, I'm thinking then T2 would be Thrust not Tension so T1+T2 = 5g? I'll give that a go and see if it's true.
Yep, that's another way to deal with it.

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