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Mathematics: Post your doubts here!

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I did. Got the wrong answer. The question is strange. I mean there is something that is supporting the weight of the ring. And it can't be friction alone, because in the very next question, we use the vertical component of the tension to balance it
Suchal Riaz Saad Mughal Any idea?
But the vertical component of the tension is supposed to point downward according to the head to tail rule
 
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on the point of sliding upwards means that the friction should act downwards and for the fricton to act downward there must be a force acting upwards which in this case is the vertical component of the tension
But that's not possible! It is implied that the horizontal points to the left...so that the normal reaction can counteract it, but then that would mean that Ta is acting in the same direction as Tc when in effect that's not true
 
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Sorry for the late reply.But here is the solution.
I-
First u can donate the tensions in AB and BC as T1 and T2 respectively.
Second,u can easily calculate the angle BAC and ACB.
BAC=53.13 ACB=36.86.
Now the resolving part.
first resolve vertically you'll get an equation like this:
T1sin53.13 + T2sin36.86=8......(i)
second resolve vertically:
T1cos53.13=T2cos36.86
0.6T1=0.8T2
T1=4/3 T2....(ii)
Equate the value of T1 in equation (i) you will get the value of T2 as 4.8N and then equate the value of T2 in equation (ii) you'll get T1 as 6.4N.
II-
Since equilibrium is limiting and ring is about to slip up the rod,Fmax is in the direction of 2N force (i.e weight of ring)
So, Fmax+2=T1cos53.13
Fmax=6.4cos53.13-2
Fmax=1.84N
uR=1.84 (Fmax=uR) and R=T1sin53.13=5.12N
u(5.12)=1.84
u=0.359.......................
I just want to give you guys an advice.While solving these type of questions u must draw a proper diagram with correct directions of each force.
 
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Sorry for the late reply.But here is the solution.
I-
First u can donate the tensions in AB and BC as T1 and T2 respectively.
Second,u can easily calculate the angle BAC and ACB.
BAC=53.13 ACB=36.86.
Now the resolving part.
first resolve vertically you'll get an equation like this:
T1sin53.13 + T2sin36.86=8......(i)
second resolve vertically:
T1cos53.13=T2cos36.86
0.6T1=0.8T2
T1=4/3 T2....(ii)
Equate the value of T1 in equation (i) you will get the value of T2 as 4.8N and then equate the value of T2 in equation (ii) you'll get T1 as 6.4N.
II-
Since equilibrium is limiting and ring is about to slip up the rod,Fmax is in the direction of 2N force (i.e weight of ring)
So, Fmax+2=T1cos53.13
Fmax=6.4cos53.13-2
Fmax=1.84N
uR=1.84 (Fmax=uR) and R=T1sin53.13=5.12N
u(5.12)=1.84
u=0.359.......................
I just want to give you guys an advice.While solving these type of questions u must draw a proper diagram with correct directions of each force.
Why didnt u take T2 cos into account un the second part?'
 
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I am very sory for late response. usama321 daredevil
please look at the diagrams and if it needs explaining tell me i will explain in greater detail.
Scan%2012-May-2014%2020.36-page1.jpg
 
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