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Section 4.5 Dynamics
Dynamics in physics explains the causes of motion. In dynamics \(v\neq 0, \quad a\neq 0,\) and \(F\neq 0\text{.}\) From Newton’s Second Law:
\begin{equation*}
\sum \vec{F} = m \vec{a}
\end{equation*}
or, equivalently
\begin{equation*}
\sum F_{x} = m a_{x}
\end{equation*}
(x-component of \(\vec{F}\)), and
\begin{equation*}
\sum F_{y} = m a_{y}
\end{equation*}
(y-component \(\vec{F}\)) For gravitational force or weight, \(F = mg\text{.}\)
