Question

A particle moving in a straight line covers half the distance with a speed of 3 $m{s}^{-1}$. The other half of the distance is covered in two equal time intervals with speeds of 4.5 $m{s}^{-1}$ and 7.5 $m{s}^{-1}$, respectively. Find the average speed of the particle during this motion.

Answer 1

$V_{avg}\frac{TD}{TT}=\frac{x}{\frac{x}{2\times 3}+\frac{x}{4}\frac{2}{9}+\frac{x}{4}\frac{2}{15}}=\frac{1}{\frac{1}{6}+\frac{1}{36}+\frac{1}{30}}=\frac{1}{\frac{30+5+6}{180}}=\frac{180}{39}=4.61m/s$