# Views of Toronto from Hamilton and Fort Niagara Illustrate Earth's Curvature

Besides that, it is admittedly quite difficult to satisfactorily demonstrate gravitational attraction outside of a relatively advanced and well-equipped laboratory, just because the forces involved on a human scale are so small, which in turn makes it easy for FEs to just call it fake and move on.
With some care, one can find the universal gravitational constant (G) within an order of magnitude using a homemade Cavendish experiment. There are a number of videos of such experiments out there.

The actual value being about 6.674 × 10⁻¹¹ Nm²/kg².

There is something charming about using rudimentary equipment to get reasonably close to such a small number. And likewise for a very large number -- Avogadro's number (≈ 6.022 × 10²³) can be found within an order of magnitude by placing a drop of oil on water and measuring the diameter of the oil patch.

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With some care, one can find the universal gravitational constant (G) within an order of magnitude using a homemade Cavendish experiment. There are a number of videos of such experiments out there.

The actual value being about 6.674 × 10⁻¹¹ Nm²/kg².

Not quite within an order of magnitude--about a factor of 14 too high--but very impressive nonetheless!

Not quite within an order of magnitude
What I said is correct: 9.018 × 10⁻¹⁰ is within an order of magnitude of 6.674 × 10⁻¹¹.

"x is within an order of magnitude of y" means they differ by a factor of about ten (italics in original):
Orders of magnitude are used to make approximate comparisons. If numbers differ by one order of magnitude, x is about ten times different in quantity than y.
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If we were to take your correction that the result of the experiment is within not one but two orders of magnitude of the accepted value, then this would be saying the result is off by a factor of about 100. It is much better to say it's off by a factor of about 10.

The "about" in "about 10" is crucial here -- the whole point of comparisons with orders of magnitude is to not engage in precise calculations. It wouldn't make sense if one were required to perform a calculation in order to warrant saying x and y are within an order of magnitude.

Moderator: Please feel free to delete this post and the one to which I replied. Off-topic and adds nothing. Actually, homemade Cavendish experiments probably deserve their own thread, as flat earthers often disbelieve gravity in some way. You could move the post with the Cavendish video to a new thread and also delete the reply quote inside it.

Besides that, it is admittedly quite difficult to satisfactorily demonstrate gravitational attraction outside of a relatively advanced and well-equipped laboratory, just because the forces involved on a human scale are so small, which in turn makes it easy for FEs to just call it fake and move on.

Some months ago I was attempting Cavendish. I don't have a laboratory so I set it up in my house. I found draft to be a huge problem, so I enclosed the lower part in a cardboard box with a hole in the top for a string. Then I found that static electricity was a huge problem, so I lined the inside of the box with metal mesh screen and used a metal cup of water with a wire hanging in it to ground all the weights to the same potential.

Then my only interference seemed to be a change in temperature on the nylon fishing line would change it's natural resting state. But that wasn't too much of a problem as long as I didn't change the temperature in my house.

I then observed that the free weights would very slowly accelerate towards the fixed weights. My setup was not conducive to actually measuring the acceleration but rough measurement seemed within a magnitude of the expected.

I hope to do the experiment again but better, just haven't had time.

Some months ago I was attempting Cavendish. I don't have a laboratory so I set it up in my house. I found draft to be a huge problem, so I enclosed the lower part in a cardboard box with a hole in the top for a string. Then I found that static electricity was a huge problem, so I lined the inside of the box with metal mesh screen and used a metal cup of water with a wire hanging in it to ground all the weights to the same potential.

Then my only interference seemed to be a change in temperature on the nylon fishing line would change it's natural resting state. But that wasn't too much of a problem as long as I didn't change the temperature in my house.

I then observed that the free weights would very slowly accelerate towards the fixed weights. My setup was not conducive to actually measuring the acceleration but rough measurement seemed within a magnitude of the expected.

I hope to do the experiment again but better, just haven't had time.
There's a fellow on YouTube who did a similar thing in setting up a Cavendish experiment, and I think was reasonably successful. Didn't follow that particular project too terribly closely, but I'm vaguely aware that he had to put a lot of time and effort into it, particularly in eliminating drafts, working out various bugs in the system, etc.

I'd need to double check my sources, but if memory serves correctly, it took Cavendish something like a year to get the experiment to operate correctly and eliminate error sources.

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