Question

A sprinter covers 100m in 11 sec startin from rest .He accelerates uniformly and attains a max velocity of 10m/s. And therafter covers the reamaining distance with uniform vel. Calculate the initial uniform acceleration and the time taken to attain maximum velocity

Answer 1

Dear student
$$\begin{gathered} Letmaximumvelocityof10m/sisobtainedafteratimetanditsaccelerationisa. \\ Formulaofdisplacementintimetis \\ {x}_1=\left(\frac{u+v}{2}\right)\times t \\ {x}_1=\left(\frac{0+10}{2}\right)\times t=5t...1 \\ timeleftfortherestofthejourneyis=(11-t) \\ Displacementinthistimeis \\ {x}_2=10\times (11-t)..2 \\ sumofdis\tan cesis=100m \\ {x}_1+x_2=100 \\ 5t+10\times (11-t)=100 \\ 5t-10t+110=100 \\ 5t=10 \\ t=2sec \\ andu\sin gtheformula \\ v=u+at \\ 10=0+a\times 2 \\ a=5m/s^2 \\ Regards \end{gathered}$$