If Fg=mg=ma and, Fg(planetX)=1/5Fg(earth)
then the time would be 5x of the time as gravity is acceleration. So 3.9s*5=19.5s
As the force of gravity is less, then the acceleration of masses is also less, therefore it will take more time for the object to fall by the factor of the force of gravity difference
Answer:
The difference between the velocity graph made walking at a steady rate means that its the same value in time, that means there's no slope on the graph, so its acceleration is 0
On the other hand, if the velocity is increasing with time, the slope of the graph becomes positive, which means that the acceleration of the particle is positive.