## Problem with tension on two strings at angles

thank you so much i get really confused with all this physics, biology is my degree so i find this all very stressful

 Quote by lilmissbossy i know this again i have done two different types of equations both giving the same answer except one is a -ve number. here are the equations Tsin(θ)+Tsin(θ)-mg=ma=0 rearranged T= sin(θ)+sin(θ)-mg T=sin(53)+sin(53)-(55kg)(9.8ms-1) T= -537.402 then i used the cos equation to check if there was any difference and this is what i got Tsin(θ)+Tcos(θ)-mg T=sin(θ)+Tcos(θ)-mg T=sin(53)+cos(53)-(55kg)(9.8ms-1) T= -537.6 i am not sure if i am rearranging the equations right or if i have the right method>>>
Confused? Don't panic! This can easily be sorted out, with so many heads on the case. Are you confused by the physics or the mathematics, or both?

-----------Physics----------------

The basic physics of the situation is:

Tsin(θ)+Tsin(θ) = mg

Are you happy with that?

-------------Mathematics-----------
This is basic algebra, just remember not to get thrown by the sin and cos!

You might find simplifying the equations useful. For instance you can say:

a = sin(θ) and b = cos(θ)

Then Tsin(θ)+Tsin(θ) = mg becomes Ta + Ta = mg

Are you happy with that?

Now the steps in the rearrangement might be clearer to you:

Ta + Ta = mg
2Ta = mg
T = mg/2a

Is that clear?

Now you can stick in the sin:

T = mg/2sin(θ)

Happy?
 yes thank you i havent really studied any math since yr 12 in 2002 or ohysics at all for that matter... so i am finding both equally confusing. that layout shows clearly what my problem was. i understand how to set that question out now lets just hope i can remember that for my exam!! Thank you
 This book is quite good for a gentle refresh of school maths (and more): http://www.amazon.com/gp/reader/0393...ef=sib_dp_ptu#

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