Q286: Question Bank - Physics Class 11 Laws of Motion Q286 Solution: Column I gives four different situations involving two blocks…
Students often treat $F_1$ and $F_2$ as positive regardless of the direction in which they act, and then write the net force as $F_2-F_1$ for the whole system. In a two‑block system the direction of the common acceleration is determined by comparing the force per unit mass of each block, i.e. by $F_1/m_1$ and $F_2/m_2$. If $m_2F_1<m_1F_2$ then $F_2/m_2>F_1/m_1$ and the system accelerates toward the block with the larger $F/m$; the sign of the acceleration must be chosen accordingly. When a force is reversed (replace $F_1$ by $-F_1$), one must also reverse the sign of the acceleration in Newton’s second law. Finally, do not confuse the tension $T$ in the connecting string with the normal reaction $N$; they satisfy different equations and have different physical meanings.
Multiple Choice Options
- A a
- B b
- C c
- D d