posted by Katie on .
If one drops a sphere and a piece of paper from the same height of 10 meters(H=10m) and the sphere hits the ground in 1.4 secs and the paper in 2 secs, what is the gravity associated with the sphere and why did the impact time change between the paper and sphere?
The sphere will have negligible aerodynamic drag compared to the weight (unless it is made of something hollow, or very light like Styrafoam). In that case
H = (1/2)gt^2 , so
g = 2H/t^2 = 10.2 m/s^2
The paper will take longer to reach the ground because aerodynamic drag will be a larger fraction of the weight. It will reach terminal velocity sooner, and tend to so from side to side if it is a flat piece of pasper.