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# Is there a reason why I can't resolve for the forces like this? watch

1. http://filestore.aqa.org.uk/subjects...2-QP-JUN14.PDF

Q(3)(a)(iv)

I understand I need to resolve the component of T that is perpendicular to the lever/rod/whatever the hell the thing is.

So initially I resolved like this (Which is correct according to the mark scheme)

But then I thought, surely if I just drew my triangle differently I could resolve like this too?

If anyone could explain why resolving it like the second picture won't work. that would be great. It's just that I don't want to be resolving incorrectly in the exam so I have thought of different ways to try and find the force.

Thanks!
2. Hi, as you said the first resolution is correct. The second one isn't correct because now T is no longer the hypotenuse. If you think about it, this means that you are saying the vertical component of T is bigger than T itself, which doesn't make sense. When resolving you need to make the force the hypotenuse Good luck with the exam
3. (Original post by TheBride)
Hi, as you said the first resolution is correct. The second one isn't correct because now T is no longer the hypotenuse. If you think about it, this means that you are saying the vertical component of T is bigger than T itself, which doesn't make sense. When resolving you need to make the force the hypotenuse Good luck with the exam
Ah I see now!

So does this mean that the force that the exam board labelled "T" is the RESULTANT force and the force I labelled in the first picture A, is the vertical component?
4. (Original post by CrazyFool229)
Ah I see now!

So does this mean that the force that the exam board labelled "T" is the RESULTANT force and the force I labelled in the first picture A, is the vertical component?
Yes A is the vertical component of T, T is the actual force causing the horizontal and vertical components, but be careful of saying "resultant" because that's used more for adding/subtracting different forces . Also thanks for the rep! Also just quickly although I said "vertical" in this case it's actually at a slight angle- but you get the gist!
5. (Original post by TheBride)
Yes A is the vertical component of T, T is the actual force causing the horizontal and vertical components, but be careful of saying "resultant" because that's used more for adding/subtracting different forces . Also thanks for the rep!
Thanks again!

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