Question

The masses $M_{1}$ , $M_{2}$ and $M_{3}$ are $5 , \, 2$ and $3 \, \text{kg}$ respectively. These have been joined using massless, inextensible pieces of strings as shown in the figure. If the whole system is going upward with an acceleration of $2$ $m \, s^{- 2}$ , then the value of tensions $T_{1},T_{2}$ and $T_{3}$ respectively are [take $g=9.8 \, m \, s^{- 2}$ ]

• A. $\text{29.4} \, \text{N, 98 N, 98 N}$
• B. $\text{98} \, \text{N, 49 N, 29.4 N}$
• C. $\text{118} \, \text{N, 59 N, 35.4 N}$
• D. $\text{35.4} \, \text{N, 118 N, 59 N}$

Answer 1

Answer: (C)

Given $T_{1}=\left(M_{1} + M_{2} + M_{3}\right)\left(\right.g+a\left.\right)$
$=\left(5 + 2 + 3\right)\left(9.8 + 2\right)=118 \, N$
$T_{2}=\left(M_{2} + M_{3}\right)\left(g + a\right)=\left(2 + 3\right)\left(9.8 + 2\right)=59 \, N$
$T_{3}=M_{3}(g+a)=3(9.8+2)=35.4 N$