Top 10 Greatest Physics Experiments: 5. Torsion Bar Experiment

The experiment was performed in 1797–98 by the English scientist Henry Cavendish. He followed a method prescribed and used apparatus built by his countryman, the geologist John Michell, who had died in 1793.
Even though Newton already had calculated the value of the gravitational constant G, it wasn’t confirmed in labarotory. This is where the torsion bar experiment comes into play.

The apparatus employed a torsion balance, essentially a stretched wire supporting spherical weights. Attraction between pairs of weights caused the wire to twist slightly, which allowed the first calculation of the value of the gravitational constant G. The experiment was popularly known as weighing the Earth because determination of G permitted calculation of the Earth's mass. The simple equation of gravity created back at the end of 17 century by Newton was confirmed once again.

Source

Source


Thanks for reading! Please subscribe and comment. Cheers!

Read more »

Top 10 Greatest Physics Experiments: 7. Foucault's Pendulum

 There were ideas that the Earth might be rotating around its axis since the days of Nicolaus Copernicus (1473 - 1543). However, even though it was a rational idea, backed up by great arguments in the works of Copernicus, it wasn’t experimentally proven. Thus many people in the middle ages and later epochs weren’t aware of the fact that our planet is rotating around its axis. After all, it’s really hard to believe such a thing, as we can’t feel the Earth’s rotation.

It was Jean Foucault (1819 - 1868) a brilliant French physicist, who finally proved Earth’s rotation experimentally, more than 300 years after the works of Copernicus. Foucault built a 28 kg brass-coated lead bob with a 67 meter long wire from the dome of the Panthéon, Paris, which basically worked as a huge pendulum. The idea of the experiment is very simple – as the pendulum swings, it’s clear that Earth rotates, due to the movement of the ground below the pendulum (which, to us looks like the movement of the plane of the pendulum, as we rotate with together with Earth).

This simple, yet very hard to construct, experiment, finally proved that Earth really rotates. Furthermore, it proved the rotation of our planet in a very simple way, so that even simple people, who knew nothing about science, could easily be convinced. That is why this experiment is one of the most important experiments throughout history.

Thanks for reading! If you like my stuff feel free to comment, follow and subscribe.

You might be interested in:

Read more »

The Most Amazing Nuclear Explosions Caught on Tape

While writing a couple of lasts articles about nuclear explosions I had a thought that I've never actually seen a real nuclear explosion caught on tape. And I'm not talking about those fake nuclear explosions in movies, I'm talking about the real deal.

So I decided to look for some great footage of nuclear explosions. Luckily I found some great footage, so I decided to share it with you guys.

So here are some amazing videos with nuclear explosions caught on tape:

First Hydrogen bomb test:

 

One of the earlier nuclear testings:

 

Underwater nuclear explosion:

 

The most powerful nuclear bomb ever tested - Tsar bomb:

And for desert - 5 biggest nukes:

Thanks for reading!

Read more »

The List of The Greatest Child Prodigies

The List of The Greatest Child Prodigies

Read more »