MCQ
If pulleys shown in the diagram are smooth and massless and $a_1$ and $a_2$ are acceleration of blocks of mass $4 \,kg$ and $8 \,kg$ respectively, then
- A$a_1=a_2$
- ✓$a_1=2 a_2$
- C$2 a_1=a_2$
- D$a_1=4 a_2$
✓
Answer
Correct option: B.
$a_1=2 a_2$
b
(b)
(b)
For $8 kg T^{\prime}=8 a_1 \ldots(i)$
for $4 kg$
$4 g-T=4 a_2 \ldots(ii)$
for pulley
$T^1=2 T \ldots(iii)$
Using $(i), (ii)$ and $(iii)$
$a_2=\frac{a_1}{2}$
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