Galileo's Experiment: Uniformly Accelerated Motion

[batballbat]

1. how can the experimental result that the distance covered by a body during free fall is directly proportional to the square of time imply that the motion is uniformly accelerated? (of course the result agrees with one of a property of uni. accelerated motion but can we show that in nonuniformly accelerated motion the distance is not proportional to time squared?)

2. galileo showed that for a free fall is uniformly accelerated. but how did he show that the acceleration which is constant for a body is same for all other bodies? (i know the statement is implied from the Newtons second law. but how did galielo conclude it?)

 

[Bill_K]

1. This one's easy! d(t) = kt², and acceleration is defined as the second derivative of d(t), which is a constant.

2. I'm not sure he did. I know he showed you get the same acceleration independent of the mass.

 

[HallsofIvy]

2) Very simple: He did the experiment many times using many diffrerent objects and always got the same value for the acceleration.