The given graph shows the position versus time for a certain object moving along the x-axis. We need to find the instantaneous velocity at 1 s. We know that the slope of position time graph gives the velocity and for a particular instant known as instantaneous velocity. Mathematically,
Taking slope of the given graph as :
At 1 s the position of the object is, and
So, the instantaneous velocity at 1 s is 3 m/s. Hence, this is the required solution.
To find instantaneous velocity given a position vs. time graph is find the derivative at that given point. In other words, find the slope at that point.