An object starts from rest and falls freely for 40. meters near the surface of planet P. If the time of fall is 4.0 seconds, what is the magnitude of the acceleration due to gravity on planet P?

Let's use the equations for rectilinear motion. One particular equation is:

d = v₀t + (1/2) at²

Since it has been mentioned that the object starts from rest, then v₀ = 0. Substituting the values,

40 m = (0) (4 s) + (1/2) (a) (4 s) ²

Solving for a,

a = 5 m/s²

Therefore, the acceleration due to gravity is 5 m/s².