Physics - Kinematics Question with Solution | TestHub

Given,$s=1.2 \mathrm{m},\mathrm{ }v=640 {\mathrm{m}\mathrm{s}}^{-1}, a=?,\mathrm{ }\mathrm{ }u=0;t=?$

We have the third equation of motion

$2as=v^2-u^2$

$2a\times 1.2=640\times 640$

Or$a=\frac{8 \times 64 \times {10}^3}{3}$

And by first equation of motion

$v=u+at$

Or$t=\frac{v}{a}=\frac{15}{4}\times {10}^{-3}$

$=3.75\times {10}^{-3}\mathrm{s}\mathrm{ }\approx 4\mathrm{ }\mathrm{m}\mathrm{s}$