A car of mass 600 kg is moving at a speed of 20 m/s. It collides with a stationary car of mass 900 kg. If the first car bounces back at 4m/s, at what speed does the second car move after the collision ?​

Vf = 16m/s

Explanation:

See image....

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.

e/c, where e is its total energy