(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

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Laws of motion question with constraint relations

**Physics Forums | Science Articles, Homework Help, Discussion**