Subsection 3.2.2 Principle of Conservation of Momentum
We have defined momentum in Subsection 2.2.3. Momentum, \(p = mv\) is also called a linear momentum as motion of the object is in straight line path. From Newton’s II law we know that \(F t = \Delta mv\text{.}\) If the force \(F\) remains zero then, \(\Delta mv = mv_f-mv_i = 0\text{.}\) This tells us that \(mv_f= mv_i\text{.}\) Meaning, if total external force acting on a system is zero, then total linear momentum of the system, \(p_t = \) constant. This is known as principle of conservation of momentum. Hence, in the case of conservaiton of mementum, final momentum of the system is equal to the initial momentum of the system i.e.,
\begin{equation}
p_i=p_f\tag{3.2.3}
\end{equation}
Newton’s Cradle Click on the link to understand the conservation of linear momentum.
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javalab.org/en/newtons_cradle_en/
