# Answer question 9

$initialvelocityu,finalvelocityu/2,displacement=3\phantom{\rule{0ex}{0ex}}a=\frac{{\displaystyle \frac{{u}^{2}}{4}}-{u}^{2}}{2*3}=-\frac{{u}^{2}}{8}\phantom{\rule{0ex}{0ex}}letthefurtherpenetrationbex\phantom{\rule{0ex}{0ex}}0=\frac{{u}^{2}}{4}-2\left(\frac{{u}^{2}}{8}\right)x\phantom{\rule{0ex}{0ex}}x=1cm\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}Regards\phantom{\rule{0ex}{0ex}}$

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