Question

Two masses of $10\,kg$ and $5\,kg$ are suspended from a rigid support as shown in figure. The system is pulled down with a force of $150\, N$ attached to the lower mass. The string attached to the support breaks and the system accelerates downwards.
If the downward force continues to act, the acceleration of the system is

• A. $20\,ms^{-1}$
• B. $10\,ms^{-1}$
• C. $5\,ms^{-2}$
• D. $zero$

Answer 1

Answer: (A)

Given,
Two masses $10 kg , 5 kg$,
F orce $=150 N$
So the acceleration of the system is $a=\frac{F_{\text {net }}}{m_1+m_2} \Rightarrow \frac{F+\left(m_1+m_2\right) g}{m_1+m_2}$
$ =\frac{150+(10+5) \times 10}{10+5}=\frac{300}{15}=20 m / s ^2 $