Answer
$9.29ft$
Work Step by Step
We can determine the required distance as follows:
According to the principle of work and energy
$\frac{1}{2}mv_1^2+\Sigma U_{1\rightarrow 2}=\frac{1}{2}mv_2^2$
$\implies \frac{1}{2}(\frac{4000}{32.2})(55)^2+U_{1\rightarrow 2}=0$
This simplifies to:
$\Sigma U_{1\rightarrow 2}=187.89kip\cdot ft$
We know that the work done can also be calculated as the area under the curve in the given figure:
$\implies \Sigma U_{1\rightarrow 2}=(2\times 9)+(5-2)\times 18+(x\times 27)$
$\implies 187.89=(2\times 9)+(5-2)\times 18+(x\times 27)$
This simplifies to:
$x=4.29ft$
Thus,
$s=x+5=4.29+5=9.29ft$
