Laws Of Motion Question 12
Question 12 - 2024 (30 Jan Shift 2)
Three blocks A, B and C are pulled on a horizontal smooth surface by a force of $80 \mathrm{~N}$ as shown in figure
| $m \mathrm{~A}$ | B | C | |||
|---|---|---|---|---|---|
| $5 \mathrm{~kg}$ | $\mathrm{~T}_{1}$ | $3 \mathrm{~kg}$ | $\mathrm{I}_{2}$ | $2 \mathrm{~kg}$ | $=80$ |
The tensions $\mathrm{T}{1}$ and $\mathrm{T}{2}$ in the string are respectively:
(1) $40 \mathrm{~N}, 64 \mathrm{~N}$
(2) $60 \mathrm{~N}, 80 \mathrm{~N}$
(3) $88 \mathrm{~N}, 96 \mathrm{~N}$
(4) $80 \mathrm{~N}, 100 \mathrm{~N}$
Show Answer
Answer: (1)
Solution:
$\mathrm{a}{\mathrm{A}}=\mathrm{a}{\mathrm{B}}=\mathrm{a}_{\mathrm{C}}=\frac{\mathrm{F}}{5+3+2}=\frac{80}{10}=8 \mathrm{~m} / \mathrm{s}^{2}$
A
$\mathrm{T}_{1}=5 \times 8=40 \xrightarrow{3} \xrightarrow{\mathrm{T}_{1}} \xrightarrow{\mathrm{T}_{2}}$
$\mathrm{T}{2}-\mathrm{T}{1}=3 \times 8 \Rightarrow \mathrm{T}_{2}=64$
