Question Number 200737 by Calculusboy last updated on 22/Nov/23
$$\boldsymbol{{Solve}}:\:\boldsymbol{{The}}\:\boldsymbol{{position}}\:\boldsymbol{{vector}}\:\boldsymbol{{of}}\:\boldsymbol{{a}}\:\boldsymbol{{particle}}\:\boldsymbol{{at}}\:\boldsymbol{{any}}\:\boldsymbol{{time}}\:\boldsymbol{{t}} \\ $$$$\boldsymbol{{is}}\:\boldsymbol{{given}}\:\boldsymbol{{by}}\:\:\underset{−} {\boldsymbol{{r}}}=\left(\boldsymbol{{acoswt}}\right)\boldsymbol{{i}}+\left(\boldsymbol{{asinwt}}\right)\boldsymbol{{j}}+\boldsymbol{{bt}}^{\mathrm{2}} \boldsymbol{{k}} \\ $$$$\left(\boldsymbol{{a}}\right)\:\boldsymbol{{show}}\:\boldsymbol{{that}},\boldsymbol{{although}}\:\boldsymbol{{the}}\:\boldsymbol{{speed}}\:\boldsymbol{{of}}\:\boldsymbol{{the}}\:\boldsymbol{{particle}} \\ $$$$\boldsymbol{{increases}}\:\boldsymbol{{with}}\:\boldsymbol{{time}},\boldsymbol{{the}}\:\boldsymbol{{magnitude}} \\ $$$$\boldsymbol{{of}}\:\boldsymbol{{the}}\:\boldsymbol{{acceleration}}\:\boldsymbol{{is}}\:\boldsymbol{{always}}\:\boldsymbol{{constant}} \\ $$$$\left(\boldsymbol{{b}}\right)\:\boldsymbol{{describe}}\:\boldsymbol{{the}}\:\boldsymbol{{motion}}\:\boldsymbol{{of}}\:\boldsymbol{{the}}\:\boldsymbol{{particle}}\:\boldsymbol{{geometrically}} \\ $$