Experiment Help: Investigating Freely Falling Bodies

AI Thread Summary
The discussion focuses on investigating the motion of a freely falling body on a fictitious planet, specifically addressing the relationship between distance fallen and elapsed time, as well as the connection between instantaneous and average velocity. For part (2), the distance fallen can be calculated using the formula d = vo*t + 1/2 a t^2, indicating that distance is proportional to the square of time under constant acceleration. In part (3), it is suggested that the average velocity can be derived from the relationship between initial and final velocities, leading to the equation d = (v_f + v_o)/2 * t. The conversation emphasizes the importance of understanding kinematics and the graphical representation of motion. Overall, the insights provided aim to clarify the physics concepts involved in the experiment.
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Experiment Help!

Homework Statement


We were given this experiment in which we have to investigate the motion of a freely falling body on a fictitious planet.

2. Things we have to do
(1) the value of the acceleration due to gravity on the planet, (sucessfully did it)
(2) how the distance fallen depends on the elapsed time, and :confused:
(3) an interesting relation between the instantaneous velocity at the center of a time interval and the average velocity over that interval. :confused:

Can anybody explain me what will be the conclusion of the part (2)
and part (3).
 
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Is there friction at the surface of the planet?
Assuming there isn't, you can still use the vector kinematics formulas.
For example, you can think about
d = vo*t + 1/2 a t^2
 
Can you give us more information on what measurements were given?
 
Since acceleration is constant, your acceleration vs time graph will look like this :

f_acceleratiom_9d47c19.png


Since acceleration is constant, the velocity changes at a constant rate every second and thus the velocity time graph is ALWAYS linear under constant acceleration like so:

f_velocitym_556c3b3.png


Note: these images are not to scale with each other.

For number 3, what is the equation for the midpoint of a line, can you you use this relationship to find an interesting equation for the relationship between the initial velocity, the final velocity, and the average velocity under constant acceleration?

A little bit of extra information since I made these graphs anyway, I want to show you another interesting relationship.

You probably notice that the distance traveled is the area under a velocity/time graph?

If you tried to compute the area of a portion of the velocity-time graph I drew you would come up with the following equation:

f_aream_fdbac81.png


For the red area, the area is v_{o}*t and for the bluish area the area can be found by \frac{1}{2}(v_{f}-v_{o})*t

Which can be combined to form d=\frac{(v_{f}-v_{o})*t}{2}+\frac{2v_{o}*t}{2} which is equal to d=\frac{(v_{f}+v_{o})*t}{2} which is a well known kinematics equation that you probably use ;-).

I added this in because you seem to enjoy developing a good understanding of physics in the other threads and the solution to #3 of your problem is very similiar. :wink:
 
Last edited:
Thanks a lot for reply and this wonderfull equation relationship!
Please be tune i am going to show u a lab experiment!
 
Did you get #2 and #3 solved? :smile:
 
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