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# Why is the answer positive? (M1)

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1. For X I got - 83 [24cos30 - 40sin60]
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2. answer gives in magnitude. you only give negative values whe they are in the opposite plane. e.g north + south -, or even north east and south west
For X I got - 83 [24cos30 - 40sin60]
You just resolved as if x were to the left ~ (40sin60 - 24cos30) would be the correct working, but you know it should be positive anyway, so if you end up with a negative answer you can usually assume it's wrong :3
4. (Original post by Kawaii289)
answer gives in magnitude. you only give negative values whe they are in the opposite plane. e.g north + south -, or even north east and south west
(Original post by Asuna Yuuki)
You just resolved as if x were to the left ~ (40sin60 - 24cos30) would be the correct working, but you know it should be positive anyway, so if you end up with a negative answer you can usually assume it's wrong :3
I'm a bit confused, aren't we supposed to always assume that 'north' and 'east' is positive?
I'm a bit confused, aren't we supposed to always assume the 'north' and 'east' is positive?
You are generally supposed to assume so yes, as it's the positive on the x/y axes, however you didn't follow that in your answer. It should be ~

X + 24cos30 = 40sin60 (equating positive and negative forces)

X = 40sin60 - 24cos30 (rearranging for X)

You just had an error with which way round to resolve your forces
6. (Original post by Asuna Yuuki)
You are generally supposed to assume so yes, as it's the positive on the x/y axes, however you didn't follow that in your answer. It should be ~

X + 24cos30 = 40sin60 (equating positive and negative forces)

X = 40sin60 - 24cos30 (rearranging for X)

You just had an error with which way round to resolve your forces
I see!! Thank you!!
I see!! Thank you!!
No problem

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