Velocity-time graph for the motion of a certain body is shown in fig. Explain the nature of this motion. Find the initial velocity and acceleration and write the equation for the variation of displacement with time. What happens to the moving body at point B? how will the body more after this moment?

Explanation

The velocity-time graph is a straight line with -ve slope, the motion is uniformly retarding one upto point B and uniformly accelerated after with -ve side of velocity axis.
At point B the vody stops and then it direction of velocity reversed.
The initial velocity at point A is `v_(0)=7ms^(-1)`
`a=(Deltav)/(Deltat)=(v_(t)-v_(0))/(Deltat)=(0-7)/(11)=-0.6364km^(-2)approx-0.64ms^(-2)`
The equation of motion for the variation of displacement with time is
`s=7t-(1)/(2)0.64t^(2)=7t-0.32t^(2)`