Answer:
[tex]a=-550.35\ m/s^2.[/tex]
Explanation:
Given :
Thickness of board , [tex]d=14 \ cm =\dfrac{14}{100000}\ km=1.4\times 10^{-4}\ km.[/tex]
Initial speed of bullet , [tex]u=450\ m/s=\dfrac{450}{1000}\ km/s=0.45\ km/s.[/tex]
Final speed of bullet , [tex]v=220\ m/s=\dfrac{220}{1000}\ km/s=0.22\ km/s.[/tex]
We know by equation of motion.
[tex]v^2-u^2=2as[/tex] ( all sign have their usual meaning )
Putting all given values we get :
[tex]0.22^2-0.45^2=2\times a\times 1.4\times 10^{-4}\\\\\dfrac{0.22^2-0.45^2}{2\times 1.4\times 10^{-4} }=a\\\\[/tex]
[tex]a=-550.35\ m/s^2.[/tex]
Hence, this is the required solution.
