Newton-second ($N \cdot s$) is the unit derived from the product of Force and Time.

1. Definition: From Newton's Second Law, Force is the rate of change of momentum ($F = \frac{\Delta p}{\Delta t}$). Rearranging this gives $\Delta p = F \times \Delta t$.
2. Impulse: The quantity Force $\times$ Time is known as Impulse, which is equal to the change in momentum.
3. Dimensional Analysis:

• Newton ($N$): Unit of Force $[MLT^{-2}]$.
• Second ($s$): Unit of Time $[T]$.
• Newton-second ($N \cdot s$): $[MLT^{-2}] \times [T] = [MLT^{-1}]$.

4. Verification: This matches the dimensions of Momentum ($p = mv$), where Mass ($kg$) $\times$ Velocity ($m/s$) gives $[M][LT^{-1}] = [MLT^{-1}]$.