Answer: B
Step-by-step explanation:
Free fall -> constant acceleration of g = 9.81ms-1
Constant acceleration -> velocity increases at a constant rate (increases proportionally with time)
Math behind it:
* Velocity is the integration of acceleration, likewise acceleration is the differentiation of velocity. Integrating a constant value gives linearly increasing function in terms of x. (integrating with respect to x)
Hence, graph B shows the trend that velocity increases at a constant rate.
Graph A - Velocity decreases linearly
Graph C - Also decreases nonlinearly
Graph D - Not possible scenario. Velocity approaches infinity.