- Home
- Standard 11
- Physics
4-1.Newton's Laws of Motion
medium
Two masses of $10\, kg$ and $20\, kg$ respectively are connected by a massless spring as shown in figure. A force of $200\, N$ acts on the $20\, kg$ mass. At the instant when the $10\, kg$ mass has an acceleration of $12\, m\, s^{-2}$, the acceleration of the $20\, kg$ mass is ...... $ms^{-2}$

A
$2$
B
$4$
C
$10$
D
$20$
Solution
If follows from the figure that the equations of motion are $:$
$200-\mathrm{f}=20 \mathrm{a}_{1}$ $\text { and } \quad f=10 a_{2}$
where $a_{1}$ and $a_{2}$ are the accelerations for $20\, kg$ and $10\, kg$ respectively.
${\text { But }} {a_{2}=12 \mathrm{ms}^{-2}}$
${\therefore \quad} {\mathrm{f}=10 \times 12=120 \mathrm{N}}$
$a_{1}=\frac{200-120}{20}=\frac{80}{20}=4 \mathrm{ms}^{-2}$
Standard 11
Physics
Similar Questions
hard