Answer to Question #186886 in Mechanics | Relativity for saad

Question

In free fall motion topic, what we will take the value of (g), either we take positive for downward motion and take negative for upward motion? kindly help me in this

thanks

Answer 1

In free fall motion the acceleration due to gravity(g), acts in downward direction i.e towards the surface of the Earth. If we visualise downward direction as negative y direction then all corresponding values of displacement, velocity should be taken as negative and so the value of acceleration due to gravity is taken negative. But if we take downward direction as positive then all the corresponding value in that direction should be take positive.