(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find :

a) acceleration of 1 kg, 2kg and 3 kg blocks and

b) tensions T1 and T2

Note: In the figure, 1, 2 and 3 represent the masses of respective blocks in Kg. T1 and T2 represent tension in strings

2. Relevant equations

Newton's laws and constraint equations

3. The attempt at a solution

Considering the uppermost pulley as a reference point, I have taken distance to :

i) mass 1 as x1,

ii) mass 2 as x2,

iii) mass 3 as x3.

From constraint considerations, T1=T2= T(say)

keeping string lengths as constant gives a1+a2+a3=0 (after a bit of solving).

Final Equations :

1) constraint equation : a1+a2+a3=0

2) for block 1 : T = -a1

3) for block 2 : 2*g - T = 2*a2

4) for block 3 : 3*g - T = 3*a3

However, the problem is that ans given in the book (DC Pandey, Mechanics Vol.1) doesn't

match with my answer.

Answer given in the book : a1 = 560/51, a2 = 590/51, a3 = 530/51 , T = 560/51 (all in SI units)

Please discuss what answers you get and how.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Laws of motion question with constraint relations

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