I need some help with the analysis of acceleration


by Cosmored
Tags: acceleration, analysis
Cosmored
Cosmored is offline
#1
Dec31-10, 08:49 AM
P: 31
At the 2:00 time mark of this video...
http://www.youtube.com/watch?v=hc7jIg7j544

...there's as formula that we're discussing on this page of another thread.
http://www.spurstalk.com/forums/show...=1#post4862796

Look what this guy says in post #1930.
What we can do is use a very exaggerated time and height, using both variables that give the most favourable result for cosmored's theory.

We are aiming for the gravity to come out with as high a figure as possible, so that when we speed it up, the sped up figures give Earth gravity or close enough.



Now, let's look at this latest example......

Gravity = 2 x height/ time squared.

To get the most favourable result, you need your heighest height estimate and your lowest time estimate.

The highest height that dust goes up estimated by you is 5ft (no way can it be higher than that, it is level with the chest camera) = 1.5 metres.

Shortest time estimate is Time = 1.2 seconds squared = 1.44

Gravity = 3 / 1.44 =2.1m s^2

Lunar gravity is 1.62m s^2



Convert the speed of the film as per cosmored x1.5 and it should be close to Earth gravity

67% = 0.8 seconds, squared = 0.64

gravity = 3 / 0.64 = 4.69m s^2 gravity


Not even half of what it should be.

With David Percy plucked from his arse x2 it is still only 8.333m s^2, sounds close but it is a big difference in terms of visibility.
Does this make any sense to anyone here? This discussion started a few pages back.

My understanding is that if we know the time and the height, we can calculate the gravity. If we know the height and the gravity, we can calculate the time. If we know the time and the gravity, we can calculate the height. If rough estimates are used for the time and the height, I can't see how this shows us anything. Am I missing something here? Any help will be appreciated. My math is a little rusty.
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Betamax
Betamax is offline
#2
Dec31-10, 09:54 AM
P: 32
Quote Quote by Cosmored View Post
At the 2:00 time mark of this video...
http://www.youtube.com/watch?v=hc7jIg7j544

...there's as formula that we're discussing on this page of another thread.
http://www.spurstalk.com/forums/show...=1#post4862796

Look what this guy says in post #1930.

Does this make any sense to anyone here? This discussion started a few pages back.

My understanding is that if we know the time and the height, we can calculate the gravity. If we know the height and the gravity, we can calculate the time. If we know the time and the gravity, we can calculate the height. If rough estimates are used for the time and the height, I can't see how this shows us anything. Am I missing something here? Any help will be appreciated. My math is a little rusty.
Hi Cosmored,

It looks like the guy you are debating with is trying to disprove your theory.

You state that the footage was slowed down to 67% to simulate gravity on the Moon, but this is incorrect. The footage would need to be slowed down to 41% to do this.

For your theory to be correct, the measurements of gravity would need to be a figure that when sped up 1.5 times would equal 9.8 metres per second per second.

That would mean the video of all the Moon walks would need to show a gravity of 4.35 metres per second. The video you seem to be discussing shows motion consistent with Moon freefall speeds. For what it's worth I can't see how your theory can be correct.

On Earth a ball will drop 4.9 metres in one second.
t = √2h/g = 1

Now you want gravity to do that drop in 1.5 seconds.
G = 2h/t^2 = 9.8/2.25 = 4.35 metres per second per second.


Hope this helps.
Cosmored
Cosmored is offline
#3
Dec31-10, 10:19 AM
P: 31
You state that the footage was slowed down to 67% to simulate gravity on the Moon, but this is incorrect. The footage would need to be slowed down to 41% to do this.
To show actual moon gravity, you are probably right. I never said the moon footage showed actual moon gravity. There are some other anomalies such as these. This is an excerpt from post #1 of the thread I posted.
-------------------------------------------------------------------------------------
There's a noticeable difference in the body movements in these two clips.
http://www.youtube.com/watch?v=wdMvQTNLaUE
http://www.hq.nasa.gov/alsj/a11/a11v.1101330.rm

What I hypothesize is that a fifty percent slow-motion was used in Apollo 11 to simulate lunar gravity. Later, they improved their methods of simulating lunar gravity and started using a combination of slow-motion and support wires. The slow-motion in the later missions might not have been exactly half-speed. It might have been sixty five or seventy percent of natural speed. It looked better but it was inconsistent with Apollo 11 footage. The inconsistency is apparent.

At around the 21 minute mark of this video the above footage from Apollo 11 can be seen played at double speed.
http://video.google.es/videoplay?doc...26565081757736

It can also be seen in this video at around the 30 minute 40 second mark.
http://video.google.com/videoplay?do...0982587487066#

(The above video "A funny thing happened on the way to the moon" keeps going on and off-line. If the above link is dead, click here)
http://video.google.es/videosearch?q...=a+funny+thin#

It looks just like movement in earth gravity.
--------------------------------
When the footage from this clip is doubled, the movements look unnaturally fast.
http://www.youtube.com/watch?v=wdMvQTNLaUE

Here it is doubled.
http://www.youtube.com/watch?v=G29WT2_y1-E

When the Apollo 11 footage is doubled, the movements look natural. This makes it very clear that they used a simple fifty percent slow-motion to simulate lunar gravity in Apollo 11 and a faster slow-motion (around 67 percent according to Jarrah White's calculations)...
http://www.youtube.com/watch?v=MW31fOWzY-E

...combined with wire supports in the later missions.
------------------------------------------------------------------------------------

How do you explain the way the Apollo 11 footage looks when the speed is doubled? The theory is that it was shown at a 50% slow-motion which might fool the public, but not scientists as it wouldn't look like real moon gravity.
Also, how do you explain the way the movement from the later missions looks when the speed is doubled? When the Apollo 11 footage is doubled in speed, the movements look like normal earth movements. When the footage from the later missions is doubled, the movements look unnaturally fast. Isn't this consistent with the theory that the Apollo 11 missions were faked with 50% slow-motion and the later missions were faked with 67% slow-motion?

Also, what do you think of what this guy says in post #1930 in that thread?
http://www.spurstalk.com/forums/show...144487&page=75
What we can do is use a very exaggerated time and height, using both variables that give the most favourable result for cosmored's theory.

We are aiming for the gravity to come out with as high a figure as possible, so that when we speed it up, the sped up figures give Earth gravity or close enough.



Now, let's look at this latest example......

Gravity = 2 x height/ time squared.

To get the most favourable result, you need your heighest height estimate and your lowest time estimate.

The highest height that dust goes up estimated by you is 5ft (no way can it be higher than that, it is level with the chest camera) = 1.5 metres.

Shortest time estimate is Time = 1.2 seconds squared = 1.44

Gravity = 3 / 1.44 =2.1m s^2

Lunar gravity is 1.62m s^2



Convert the speed of the film as per cosmored x1.5 and it should be close to Earth gravity

67% = 0.8 seconds, squared = 0.64

gravity = 3 / 0.64 = 4.69m s^2 gravity


Not even half of what it should be.

With David Percy plucked from his arse x2 it is still only 8.333m s^2, sounds close but it is a big difference in terms of visibility.
Does this make any sense to you?

Thanks for answering. Any help is appreciated.

Betamax
Betamax is offline
#4
Dec31-10, 11:16 AM
P: 32

I need some help with the analysis of acceleration


Quote Quote by Cosmored View Post
To show actual moon gravity, you are probably right. I never said the moon footage showed actual moon gravity.
*snip*
Wowie, that's an awful lot of questions!

Firstly, I already answered your first post - the figures are correct. The guy seems to be attempting to show that the footage sped up does not show Earth gravity.

I have to agree with him. For the most part, any footage I have seen of the Moon missions looks pretty much as it would under 1/6th Earth gravity. I really don't want to get into a debate on whether you think it was a hoax, as that is just nonsense.

The only point I can address and will address in your list is the speeded up 2 times for Apollo 11.
Back to the math from my other post:-

On Earth a ball will drop 4.9 metres in one second.
t = √2h/g = 1

Now you want gravity to do that drop in 2.0 seconds.
G = 2h/t^2 = 9.8/4 = 2.45 metres per second per second.

If you want it to equal Moon gravity do that drop in 2.45 seconds.
G = 2h/t^2 = 9.8/6.0025 = 1.63 metres per second per second.

I guess if you want to prove Apollo 11 is half speed, you will need to show gravity of 2.45 metres per second per second.
Cosmored
Cosmored is offline
#5
Dec31-10, 12:06 PM
P: 31
I guess if you want to prove Apollo 11 is half speed, you will need to show gravity of 2.45 metres per second per second.
I don't know of any Apollo 11 footage that shows dropped objects. Also, how could we measure the distance precisely and time the drop precisely?

The last throw in this clip is the only one that we can see head on.
http://www.youtube.com/watch?v=isVO9AAAhxM

How could we get a precise measure of the distance and the speed?

Once we have the precise measurements, we could plug them into equations such as these.
http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html
Betamax
Betamax is offline
#6
Dec31-10, 03:00 PM
P: 32
Quote Quote by Cosmored View Post
I don't know of any Apollo 11 footage that shows dropped objects. Also, how could we measure the distance precisely and time the drop precisely?

The last throw in this clip is the only one that we can see head on.
http://www.youtube.com/watch?v=isVO9AAAhxM

How could we get a precise measure of the distance and the speed?
If somebody asked me to do this as a project, I would first of all download the clips and put them into a player such as Windows Movie Maker. You then time the motion to or from apex. That would be pretty precise for the time.

The height is just going to be guesswork. Again if it were me, I would use the old friend Occam's razer. I would run the figures for Moon gravity and determine the height.

At this point you should be able to look at each piece of footage and determine whether the height from each equation is a good ball park figure, or whether it is significantly and provably wrong. If it looks fairly accurate, you would have to say the footage is filmed in a 1/6th gravity. If it wasn't, you would suspect a problem.

Just doing some rough figures on those clips, they look pretty consistent with Moon gravity.

One final thing I would suggest is that you speed the clip up 150% as you claim, and take your readings from that. According to your theory they should all be Earth freefall speeds.

I am totally biased since this conspiracy is one of the silliest I have ever seen, but those clips are not falling at Earth freefall even with the speed doubled. Now you may ask me how I can be so sure, the answer is on the same channel as the clip you showed:-

http://www.youtube.com/user/bertlapo.../1/ZnP2ek47KRI

That is not Earth freefall speed it is too slow, even visually. Case proven.
Cosmored
Cosmored is offline
#7
Jan2-11, 04:44 AM
P: 31
Thanks Betamax. This will give me something to analyze for a while. There's one more thing though–the proof in post #1.

I might be mistaken but I think there's a flaw in his calculations.

If I'm not mistaken, if you want to calculate the gravity with the 5 ft height figure, the time that it takes an object to fall 5 ft has to be measured very precisely. Then we plug the height and time figures into the gravity equation (Gravity equals height doubled divided by time squared).

If we want to calculate the gravity with the 1.2 time figure, we have to precisely measure an object falling for the first 1.2 seconds and then precisely calculate the distance it took. Then we have to plug those two figures into the gravity equation.

If I'm not mistaken, if you take to estimates that don't correspond to each other, it will yield a meaningless figure.

Am I right, about this? Do you think the work I posted in post #1 is valid?
Cosmored
Cosmored is offline
#8
Jan2-11, 05:16 AM
P: 31
You then time the motion to or from apex. That would be pretty precise for the time.

The height is just going to be guesswork. Again if it were me, I would use the old friend Occam's razer. I would run the figures for Moon gravity and determine the height.
I may be wrong but, if you're going to measure the time while assuming it's moon gravity, if it really is 67% slow-motion, won't the figure for time be wrong?

I want to thank you for being patient with me; it's been years since I did any serious math and I'm pretty rusty. Even then, I had a hard time visualizing things. When we did max-min problems, I could work out the equations with no problem but when I had to take a situation and form the equation, I could only do the simplest ones.
Betamax
Betamax is offline
#9
Jan2-11, 09:43 AM
P: 32
Quote Quote by Cosmored View Post
Thanks Betamax. This will give me something to analyze for a while. There's one more thing though–the proof in post #1.

I might be mistaken but I think there's a flaw in his calculations.

If I'm not mistaken, if you want to calculate the gravity with the 5 ft height figure, the time that it takes an object to fall 5 ft has to be measured very precisely. Then we plug the height and time figures into the gravity equation (Gravity equals height doubled divided by time squared).

If we want to calculate the gravity with the 1.2 time figure, we have to precisely measure an object falling for the first 1.2 seconds and then precisely calculate the distance it took. Then we have to plug those two figures into the gravity equation.

If I'm not mistaken, if you take to estimates that don't correspond to each other, it will yield a meaningless figure.

Am I right, about this? Do you think the work I posted in post #1 is valid?
Hi Cosmored,

You are over thinking this. If the objective is to take accurate figures of freefall, you obviously need 2 components to be precise.

In the case you present, the object appears to be to obtain a figure that should represent your theory. The figures in your first post are accurate enough.

You have your theory that the footage has been filmed in Earth gravity, which as you know is 9.8m s^2. Now when you slow the footage by 67% to try to hoax Moon gravity, that isn't going to work. You are going to see 4.35m s^2 (I did the math in the post above).

Conversely if you take the footage as presented, it needs to show freefall of 4.35m s^2, so that when you speed the film up 150%, it becomes 9.8m s^2.

From what I can see of the exchange in that thread, your opponent is attempting to disprove your theory, by taking a range of figures and using the limits that give the highest possible gravity.

Taken from your quote in post#1:-
To get the most favourable result, you need your highest height estimate and your lowest time estimate.
I can confirm that statement as true. It basically puts the highest number (numerator) in the top of the division and the lowest one in the bottom (denominator). This gives the highest number.

Example:- 4/3 and 5/2 = 1.333 and 2.5 respectively.


I hope this helps.
Betamax
Betamax is offline
#10
Jan2-11, 09:51 AM
P: 32
Quote Quote by Cosmored View Post
I may be wrong but, if you're going to measure the time while assuming it's moon gravity, if it really is 67% slow-motion, won't the figure for time be wrong?
You simply take the time and height from the footage presented, whatever speed it runs at.

If you want to work out the time when it is sped up you need to divide the time component by the factor you speed it up by.

Examples:-
Time normal is 1.5 seconds. Speed up 1.5 = 1.5/1.5 = 1
Time normal is 1 second. Speed up 1.5 = 1/1.5 = 0.666
Cosmored
Cosmored is offline
#11
Jan2-11, 03:51 PM
P: 31

To get the most favourable result, you need your highest height estimate and your lowest time estimate.
-----------------------
I can confirm that statement as true. It basically puts the highest number (numerator) in the top of the division and the lowest one in the bottom (denominator). This gives the highest number.
There's one thing I'd like to clarify.

Don't the figures have to be tested with figures that correspond to them? It seems to me that two rough estimates for height and time aren't going to correspond and are going to give a meaningless figure for gravity. To test whether the figure for height is valid, wouldn't we have to precisely measure the time it takes an object to fall that far in the footage and then plug those two figures into the gravity formula? And to test whether the figure for time is valid, wouldn't we have to precisely measure the distance covered in said time and then plug that and the time figure into the formula for gravity?

Maybe I'm missing something but I just can't visualize how plugging the rough estimations for height and time into the gravity formula is going to give a valid figure for gravity. My common sense tells me those two figures would have to be tested in separate equations–not the same equation.

I haven't done any serious math for years so I hope you'll be patient with me.
Betamax
Betamax is offline
#12
Jan3-11, 03:28 AM
P: 32
Quote Quote by Cosmored View Post
There's one thing I'd like to clarify.

Don't the figures have to be tested with figures that correspond to them? It seems to me that two rough estimates for height and time aren't going to correspond and are going to give a meaningless figure for gravity. To test whether the figure for height is valid, wouldn't we have to precisely measure the time it takes an object to fall that far in the footage and then plug those two figures into the gravity formula? And to test whether the figure for time is valid, wouldn't we have to precisely measure the distance covered in said time and then plug that and the time figure into the formula for gravity?

Maybe I'm missing something but I just can't visualize how plugging the rough estimations for height and time into the gravity formula is going to give a valid figure for gravity. My common sense tells me those two figures would have to be tested in separate equations–not the same equation.

I haven't done any serious math for years so I hope you'll be patient with me.
Hi Cosmored,

You are getting confused with definitive gravity for the Moon or Earth and speculative figures from data ranges.

This is exactly how you determine a range of potential values, you look at highest and lowest variables then take combinations of equations accordingly. What you get is the highest value possible, and the lowest value possible.

If the objective was to take figures that correlate with Moon gravity, a certain height will require a certain time, and a certain time will require a certain height. But you don't want that when you are trying to find the highest figure attainable for gravity, from two ranges of figures.

I'm not sure what else I can say on this, it all seems fairly straightforward.

Best of luck
Cosmored
Cosmored is offline
#13
Jan5-11, 12:41 PM
P: 31
I appreciate all your help Betamax.

From what I can see of the exchange in that thread, your opponent is attempting to disprove your theory, by taking a range of figures and using the limits that give the highest possible gravity.
Do you think he has actually proven that the footage couldn't be earth gravity slowed to 67%? This is from post #1983 on page 77.
If you plug in the heighest height and the lowest time that is the highest gravity you can obtain. If you plug the lowest height and the longest time in, that is the lowest gravity you can obtain.

All taken from Apollo footage. If you then convert the highest gravity you can get to your formula x1.5 (Jarrah White's actually), it is nowhere near Earth gravity.

Any combination of any of the heights or times between the ranges you gave will fall between the maximum it can be and the minimum it can be.
http://www.spurstalk.com/forums/show...144487&page=77
Betamax
Betamax is offline
#14
Jan5-11, 02:50 PM
P: 32
Quote Quote by Cosmored View Post
I appreciate all your help Betamax.
Do you think he has actually proven that the footage couldn't be earth gravity slowed to 67%?
Hi Cosmored,

I would have to say that based on the figures presented and the ranges that they produce, your theory of footage slowed down to 67% is untenable.

As I showed with a little math from post 1:-

On Earth a ball will drop 4.9 metres in one second.
t = √2h/g = 1

Now you want gravity to do that drop in 1.5 seconds.
G = 2h/t^2 = 9.8/2.25 = 4.35 metres per second per second.

For your theory to hold up, the gravity must be 4.35m s^2 in the visible footage, as when sped up 150% it then becomes 9.8m s^2. As I also said previously, most of the thrown items are roughly in the correct order of magnitude for Moon gravity.

Your goal is to find a piece of footage that shows that freefall speed of 4.35m s^2, otherwise I'm afraid your theory is unsupportable.

Best regards and a Happy New Year to you.
Cosmored
Cosmored is offline
#15
Jan5-11, 03:09 PM
P: 31
Thanks for your input. I've never seen any precise measurements for movements on the moon. There's one that looks easy to measure at the 9:00 time mark in this clip.
http://www.youtube.com/watch?v=JBICR4PTLfc

I don't know how to use Windows Movie Maker. I think this is up in the air until we can be sure that we have some precise measurements. I think the visual evidence in my second post pretty much shows fakery without doing any calculations anyway.
Cosmored
Cosmored is offline
#16
Jan6-11, 05:55 AM
P: 31
I appreciate your help Betamax. There's one thing on which I'm still not clear. This proof that I posted in post #1.
What we can do is use a very exaggerated time and height, using both variables that give the most favourable result for cosmored's theory.

We are aiming for the gravity to come out with as high a figure as possible, so that when we speed it up, the sped up figures give Earth gravity or close enough.



Now, let's look at this latest example......

Gravity = 2 x height/ time squared.

To get the most favourable result, you need your heighest height estimate and your lowest time estimate.

The highest height that dust goes up estimated by you is 5ft (no way can it be higher than that, it is level with the chest camera) = 1.5 metres.

Shortest time estimate is Time = 1.2 seconds squared = 1.44

Gravity = 3 / 1.44 =2.1m s^2

Lunar gravity is 1.62m s^2



Convert the speed of the film as per cosmored x1.5 and it should be close to Earth gravity

67% = 0.8 seconds, squared = 0.64

gravity = 3 / 0.64 = 4.69m s^2 gravity


Not even half of what it should be.

With David Percy plucked from his arse x2 it is still only 8.333m s^2, sounds close but it is a big difference in terms of visibility.
I thought this made no sense at all but you said this.
You are getting confused with definitive gravity for the Moon or Earth and speculative figures from data ranges.
I have to admit that I'm still confused. Do you think this person actually proved that the footage in this video...
http://www.youtube.com/watch?v=hc7jIg7j544
(1:00 time mark)

... couldn't possible have been filmed on earth and slowed to 67 percent slow-motion with the above proof? Also, in what math course is the idea of "Speculative figures from data ranges" in a situation such as this studied? I took algebra, trig, and the first semester of calculus thirty years ago and I don't recall ever seeing this. This is a whole new concept for me.

You seem to know your math. I hope this request isn't a lot of trouble.

Thanks
Betamax
Betamax is offline
#17
Jan6-11, 09:17 AM
P: 32
Quote Quote by Cosmored View Post
I appreciate your help Betamax. There's one thing on which I'm still not clear. This proof that I posted in post #1.


I thought this made no sense at all but you said this.


I have to admit that I'm still confused. Do you think this person actually proved that the footage in this video...
http://www.youtube.com/watch?v=hc7jIg7j544
(1:00 time mark)

... couldn't possible have been filmed on earth and slowed to 67 percent slow-motion with the above proof? Also, in what math course is the idea of "Speculative figures from data ranges" in a situation such as this studied? I took algebra, trig, and the first semester of calculus thirty years ago and I don't recall ever seeing this. This is a whole new concept for me.

You seem to know your math. I hope this request isn't a lot of trouble.

Thanks
Hi Cosmored,

The figures quoted in your first post look very reasonable, and the math is correct.

Your opponent is doing what you yourself should do to prove your theory. He has taken the highest and lowest heights and times that could reasonably be deduced and taken the ones most likely to prove your case. They should equate to 4.35m s^2 or very close to that, so that when sped up by 150% they then equate to Earth's 9.8m s^2.

The "speculative" reference was in relation to the ranges of figures deduced by reasonable estimate, which in turn were used to produce a range of highest and lowest gravity readings obtainable.

As can clearly be seen they do not come close to that figure, so I would say your opponent has proven your theory is incorrect. Indeed, from my own perspective, the motion is entirely consistent with what one would expect on the Lunar surface.
Cosmored
Cosmored is offline
#18
Jan6-11, 03:37 PM
P: 31
Sorry to bother you again Betamax. I have to say that I still don't understand this method of verifying whether the height and speed of a falling object are consistent with moon gravity, or with earth footage shown at 67% slow-motion. In what math course is this method covered. I don't remember having seen it used anywhere. The only way I can see to calculate on what planet an object is when it falls is to precisely measure the height and time and plug the figures into the gravity formula. If it's the moon, it will yield a figure of somewhere around 1.66. If it's 67% slow-motion of earth footage, the figure will be around 4.37. I just can't visualize how taking the maximum possible height and the lowest possible time and plugging them into the gravity formula will tell us anything. Isn't the gravity formula only for calculating gravity with precisely measured heights and times?


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