Question Number 14246 by tawa tawa last updated on 30/May/17
Commented by ajfour last updated on 30/May/17
Commented by ajfour last updated on 30/May/17
$${a}=\frac{{v}−{u}}{\Delta{t}}\:=\frac{\mathrm{25}−\mathrm{30}}{\mathrm{3}}=−\frac{\mathrm{5}}{\mathrm{3}}{m}/{s}^{\mathrm{2}} \\ $$$${let}\:{total}\:{time}\:{to}\:{stop}\:{be}\:{T},\:{then} \\ $$$${from}\:\boldsymbol{{v}}=\boldsymbol{{u}}+\boldsymbol{{at}} \\ $$$$\mathrm{0}=\mathrm{30}−\frac{\mathrm{5}}{\mathrm{3}}{T}\:\:\:\:\Rightarrow\:{T}=\mathrm{18}{s} \\ $$$${and}\:{from}:\:\:\boldsymbol{{s}}=\boldsymbol{{ut}}+\frac{\mathrm{1}}{\mathrm{2}}\boldsymbol{{at}}^{\mathrm{2}} \\ $$$$\:{distance}=\mathrm{30}×\mathrm{18}−\left(\frac{\mathrm{1}}{\mathrm{2}}\right)\left(\frac{\mathrm{5}}{\mathrm{3}}\right)\left(\mathrm{18}\right)^{\mathrm{2}} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\mathrm{540}−\mathrm{270}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\mathrm{270}{m}\:. \\ $$
Commented by tawa tawa last updated on 30/May/17
$$\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir}. \\ $$
Answered by ajfour last updated on 30/May/17
Commented by ajfour last updated on 30/May/17
$$\left(\mathrm{2}{A}\right)^{\mathrm{2}} +{A}^{\mathrm{2}} =\mathrm{64} \\ $$$$\mathrm{5}{A}^{\mathrm{2}} =\mathrm{64} \\ $$$${A}=\frac{\mathrm{8}}{\sqrt{\mathrm{5}}}\:\:. \\ $$
Commented by tawa tawa last updated on 30/May/17
$$\mathrm{Thanks}\:\mathrm{for}\:\mathrm{everytime}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir}. \\ $$