Priyanka B Solutions for Chapter: Motion, Exercise 6: Practice Problems

A body moves with a velocity of $2 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ for $5 \mathrm{s}$. Then its velocity increases uniformly to $10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ in the next $5 \mathrm{s}$. Thereafter its velocity begins to decrease at a uniform rate until it comes to rest after $10 \mathrm{s}$. Plot a velocity-time graph.

A body moves with a velocity of $2 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ for $5 \mathrm{s}$. Then its velocity increases uniformly to $10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ in the next $5 \mathrm{s}$. Thereafter, its velocity begins to decrease at a uniform rate until it comes to rest after $10 \mathrm{s}$. Mark the portions of the graph of uniform motion and non-uniform motion.

A body moves with a velocity of $2 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ for $5 \mathrm{s}$. Then its velocity increases uniformly to $10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ in the next $5 \mathrm{s}$. Thereafter, its velocity begins to decrease at a uniform rate until it comes to rest after $10 \mathrm{s}$. From the graph, find the total distance moved by the body in the initial $5 \mathrm{s}$ and the initial $12 \mathrm{s}$ and in the last $10 \mathrm{s}$.

A sprinter in a $100 \mathrm{m}$ race covers $4 \mathrm{m}$ in the first second, $30 \mathrm{m}$ in the next $4 \mathrm{s}$, $52 \mathrm{m}$ in another $4 \mathrm{s}$ and finishes the race in $10 \mathrm{s}$.  Calculate the average velocity of the sprinter. You may assume that at any given time interval, velocity is uniform.

A sprinter in a $100 \mathrm{m}$ race covers $4 \mathrm{m}$ in the first second, $30 \mathrm{m}$ in the next $4 \mathrm{s}$, $52 \mathrm{m}$ in another $4 \mathrm{s}$ and finishes the race in $10 \mathrm{s}$. In which time interval, is the average velocity attained by the sprinter maximum? State this velocity in appropriate units.

A sprinter in a $100 \mathrm{m}$ race covers $4 \mathrm{m}$ in the first second, $30 \mathrm{m}$ in the next $4 \mathrm{s}$, $52 \mathrm{m}$ in another $4 \mathrm{s}$ and finishes the race in $10 \mathrm{s}$. Plot the distance-time graph for the motion of the sprinter. Assume uniform velocity at all times.

A sprinter in a $100 \mathrm{m}$ race covers $4 \mathrm{m}$ in the first second, $30 \mathrm{m}$ in the next $4 \mathrm{s}$, $52 \mathrm{m}$ in another $4 \mathrm{s}$ and finishes the race in $10 \mathrm{s}$. Find out the distance moved by the sprinter at the end of $6 \mathrm{s}$ with the help of the graph.

Discuss the graphs $A$,$B$ and $C$ as shown in the figure. Compare the total distance traveled and the displacements. Which portion of the graph represents a motion in which the displacement is zero?