A car is moving along a straight line $O P$ as shown in the figure. It moves from $O$ to $P$ in 18 s

Question

A car is moving along a straight line $O P$ as shown in the figure. It moves from $O$ to $P$ in 18 s and returns from $P$ to $Q$ in 6 s . Which of the following statements is not correct regarding the motion of the car ?

Professor PC Thomas Classes · Answer

(d) : From $O$ to $P$ and come back to $Q$ Average speed\ $ =\frac{	ext { Path length }}{	ext { Time interval }}=\frac{O P+P Q}{\Delta t}=\frac{(360+120) \mathrm{m}}{24 \mathrm{~s}}=20 \mathrm{~ms}^{-1} $\ $ 	ext { Average velocity }=\frac{	ext { Displacement }}{	ext { Time interval }}=\frac{240 \mathrm{~m}}{24 \mathrm{~s}}=10 \mathrm{~m} \mathrm{~s}^{-1} $\ From $O$ to $P$ and come back to $O$\ $ 	ext { Average speed }=\frac{360 \mathrm{~m}+360 \mathrm{~m}}{36 \mathrm{~s}}=20 \mathrm{~m} \mathrm{~s}^{-1} $\ Average velocity $=\frac{0 \mathrm{~m}}{36 \mathrm{~s}}=$ zero