Galileo’s Paradox

By Anupum Pant

Here’s an image of a contraption. It is basically a long stick hinged at one end and is free to move about the other. At the end of it rests a ball. Near the ball there’s also a cup fastened to the stick. The big stick is lifted up high and is temporarily supported by a small stick.

galileo paradox

Now, what do you think would happen when the temporary support is removed? Normally, it would be very intuitive to think that the cup and the ball would fall at the same speed. In other words, nothing fascinating would happen. Both would fall and the ball would roll away…no?

However, something very unexpected happens when the support is removed. Something that, in a jiffy demonstrates some very important concepts of physics like centre of mass, torque and acceleration.

The big wooden stick (with the fastened cup) falls and it falls faster than the ball. Actually it falls and also rotates. As a result of the swing, the cup comes under the ball just before ball reaches it and the ball ends up inside it.

Under the influence of the same gravitational force, irrespective of the mass, the cup and the ball must have fallen at the same rate, as predicted by Galileo? What really happens? The video explains…

Evolution of Eggs

By Anupum Pant

Eggs come in a variety of shapes, sizes and colours. Birds, a major group of creatures that descended from reptiles have, for several years, continued to evolve the design of their eggs for millions of years now (not consciously, through natural selection).

Eggs could have been cube shaped. In that case they would have been very difficult to lay. Also, they would have been weakest at the centre points of a face of the cube. Hence, eggs didn’t end up being squarish.

While most eggs have evolved to, well, an egg-shape, some eggs like those of some owls are nearly spherical in shape. But oval and pointy eggs do have an advantage of sort.

Spherical eggs tend to roll easily, and if laid somewhere near a cliff, they’d roll away, never to be seen ever again. Oval eggs normally tend to roll in circles. Usually, they roll in big circles. Still dangerous for birds who perch on cliffs most of the time.

Of all the eggs, the egg of a common guillemot bird is probably the most incredible – in the sense that it has a design that doesn’t let it roll down cliffs very easily.

Common guillemots are sea birds and they normally like to perch on cliffs. To add to the danger of their precarious perching places, they usually perch on such cliffs with a huge group. Also, they don’t even make nests.

Had their eggs been shaped like those of owls, they would have easily gotten knocked by someone from that huge group of perching birds, perching on precarious cliffs. So, their eggs have evolved to survive these conditions.

This is how their eggs look like. They are very awkwardly shaped. But when it rolls, thanks to natural selection, it rolls in very small circles! They don’t fall off cliffs easily. Wonderful!

common guillemot egg

First seen at [io9]

Everyone Knows Magnet in a Copper Tube, But this…

By Anupum Pant

I’m sure you know that if you let a strong magnet drop along a thick copper tube, the magnet falls in a very interesting manner. It falls slower than it normally should, delaying the span of the fall, as if gravity acting on the magnet mysteriously drops. If you haven’t heard about it, I’ll give it to you, you probably aren’t a YouTube addict, and that’s definitely good (and maybe also bad because there’s awesome stuff out there which you are missing). Just watch this, what I just said will start making sense…

Why does this happen?

OK, that’s pretty cool, but you knew about this little magnet-copper trick already, and you were expecting something more? You got it.

Whatever you just saw neither was a magic trick, nor was the Copper tube acting as an anti-gravity machine. This is pure science, can be easily explained by it. Here…

When a magnet moves quickly near a metal, it generates current in the metal. Here, current is generated in the Copper tube.
The current generated in the tube generates another magnetic field which opposes the magnetic field of the magnet and pushes the magnet upwards, away from the force of gravity. Gravity being stronger, pulls it down, but not with as much force because the magnet is being pushed in the other direction too. That’s the simple science behind it.
Still, someone else could explain it better on a page which is completely dedicated to explain it to you. [Here] and [Here]

But, you probably knew even that -The trick and the science behind it. So, there’s more for your-kind-of-people.

A new skill-toy that uses the same…

Feel flux. An amazing new skill toy that works on the same principle. Who would have thought, playing with gravity could get fun. The crowd funding campaign for it runs on indiegogo. Go fund it!