Define 'average speed'. An object moves with a uniform speed of $10\, m s ^{-1}$ for $5 s$ and then with a uniform speed of $5\, m s ^{-1}$ for $10\, s$. Find its average speed.
Define acceleration. State a relationship connecting $u, v, a$ and $t$ for an accelerated motion. Give an example of a motion in which acceleration is uniform.
Area under velocity$-$time graph is equal to the
Study the given graph and answer the following questions
$(i)$ Which part of the graph shows accelerated motion ?
$(ii)$ Which part of the graph shows retarded motion ?
$(iii)$ Calculate the distance travelled by the body in first $4$ seconds of journey graphically.
The distance$-$time graph of two trains are given below. The trains start simultaneously in the same direction.
$(i)$ How much ahead of $A$ is $B$ when the motion starts ?
$(ii)$ What is the speed of $B$ ?
$(iii)$ When and where $A$ will catch $B$ ?
$(iv)$ What is the difference between the speeds of $A$ and $B$ ?
$(v)$ Is the speed of either trains uniform or non uniform ? Justify your answer.