Do you believe in Newton's gravitational law?

Question

I have read that the G constant from F=G(m1m2)/r2
was only measured after the death of Newton, by a public entertainer named Cavendish.

However !!! the lead balls used in Cavendish's experiment could have been charged wih electricity, and moved towards each other without the use of a "gravitational force"... one accidental contact can ponctually charge lead, which is a poor electricity conductor. It's electronegativity alone may even affect the two balls.

From there, could we simply have mistaken gravitation and magnetism? And how can we prove that the gravition law is real aside from testing it on the moon and on the earth? (with a hypothetical mass again for the earth and the moon).

Cavendish could have set a standard which is right for the moon and the earth (if we assume their estimated mass is exact too), yet not for other planets. Newton himself did not identify what causes gravitation. And Einstein only muttered about the curve of space and time. What about you?

Newton's 3rd law:
http://en.wikipedia.org/wiki/Newton%27s_gravitational_law

Lead properties:
http://en.wikipedia.org/wiki/Lead

Answer 1

You are at the hart the true science by asking this question. Take nothing for granted and reexamine the obvious. Indeed!

Your doubt is easy to overcome by introducing a conducting strip between the torsional wire, which is connected to the suspended lead balls and the other stationary masses. That should equate the potential, should it not?

Curious is that in reality Henry Cavendish by being both of noble birth and some what asocial behavior would strongly object to being called an entertainer.

Curious is that he used and improved upon the apparatus originally developed by John Michell.

As far as gravity is concerned I think it simply sucks!

Answer 2

There is zero prospect that there is any confusion between electrostatics (the magentic force is just a relativistic correction to electrostatics) and gravity. Its hard to know here to begin with your misconceptions.

On the Cavendish apparatus - the balls are electrically connected, so there can be no charge difference.

On Newton - he tested the law on the motion of the moon.

But the main nail in the coffin of your idea is simple. Gravity - unlike electrostatics - acts on bodies regardless of charge (so it does not vary as charge varies) and is proportional to mass. We could not mistake this for another force because it is this very dependence on mass and the dependence of acceleration under a force on mass that means all bodies fall at the same rate - an experiment you can do trivially from your bedroom window.

Answer 3

Well, the gravitational constant appears to work, but like you said, there is no real known reason for gravity to exist.
It could very well be a fluke, or a mistake. Formulas for Magnetic attraction are very close to the ones for gravitational attraction, so you might be onto something.

However, Im going to use Newtons laws of physics until something better comes along.

Answer 4

First of all, your note about Cavendish is incorrect. (see reference)

Second of all, Einstein explained why gravity can and does "exist". His "muttering" has more weight than your argument from incredulity does as it stands up to emperical testing.

The laws of gravity are tested every time one gets out of bed in the morning.

It is good to have an open mind, but not so open your brain falls out.

Answer 5

No scientific theories or laws are "proven". All remain permanently available for revision or even refutation. The theory that the Earth is roughly a globe, the theory that it orbits the Sun, neither of those theories are proven. However, the evidence presently indicates they're correct. Science doesn't work by proving things. The process involves attempted falsification.

Answer 6

Why Not If You Excuse The Oddities And Anomolies On A Cosmological Scale

Answer 7

the fact of the earth core is that it is a metal. But we are not sure that it is...we only experiment and see what it really is.

So we are not sure if it is magnification.

Though the core does not prove that it has magnetism but it has a strong force pushing down that is gravity.

Gravity must be made bacause the planet has a very small black hole. Actually that is what it is! Black holes!Yet it is not big enough to suck a star.

So that means gravity is true.

Answer 8

It seems that you accept that two similar charges are repelled and obeys Coloumb's law of elctrostatic forces.

Whether one believes or not, two masses ( gravitational mass) exactly obey Newton's law of gravitation.

Answer 9

The next time you get glassy and decide to dance on a table remember: Gravity is not just a good idea---it's the law!

Answer 10

its a law already duh???? i didnt read your extra details...too long!!!