Tag: electric

Making Xrays Using a Sticky Tape

By Anupum Pant

It’s been known since the 1950s that peeling a sticky tape can produce great amounts of energy. But it wasn’t until recently (in the year 2009) a few scientists, who also didn’t quite believe what sticky tapes could do, decided to actually test this phenomenon.

Astoundingly, a simple act of peeling an adhesive tape, can produce enough xrays to make a Geiger counter cry like a cricket.

In fact, the xrays produced by peeling off sticky tape at the rate of about 5cm per second inside an evacuated chamber can produce enough xrays that can expose a photographic film – enabling you to take an xray of your finger – as demonstrated by the researchers in the video below.

The video is fairly old, was uploaded in the year 2009 and I somehow have never stumbled upon it. It seems relevant even today. Thanks to ScienceDump for showing me this today.

Imagine, you can take an xray picture of your finger using a simple adhesive tape (peeling off in vacuum of course). Scientists possibly couldn’t have discovered a cheaper source of producing xrays.

The vacuum is needed to let enough charge to accumulate before the medium in between the charges breaks. Had the peeling been done in atmospheric pressure, it would have just produced visible light (lower energy than xrays). You can even try doing that at home. Go to a dark room and try peeling off a sticky tape quickly. Thanks to the effect called triboluminescence, you’ll be able to see a spark of light coming out!

Platypus is a Very Strange Animal!

By Anupum Pant

Background

What would you get if you if you crossed a duck, frog & snake? Hint: It is a mammal and lays eggs!
You’d have one of the most weirdest and mysterious animal, the Platypus.

Knuckles the echinda.pngNote: Unlike what is popularly taught in schools, Platypus is not the “only mammal that lays eggs”. Echidna – Knuckles from Sonic the Hedgehog – is the second kind of mammal that lay eggs.

So, Platypus is considered a strange animal because, it secretive and even today, not everything is known about it. It has a beak that looks like a duck’s beak, it’s feet are webbed like that of a frog’s. Besides that, this cute & cuddly looking creature, found in the Eastern part of Australian fresh waters, uses venom like a snake. But there is more:

Some Incredible things about the Platypus

Firstly, it lays eggs and is not a reptile. It is one of those two mammals which lays eggs.

For up to 3 months the male Platypus stores the eggs in its bill.

They swim underwater with their eyes shut and come out mostly at night.

Venom: They have a sharp and hollow thumbnail (spur) in their hind legs that is venomous. The venom is strong enough to kill a dog (doesn’t kill humans, but is extremely painful). This is used only in self defense. And only males are venomous. I never knew they had venom, but since they are from Australia, I had expected that.

Electrolocation: Under water, they detect electrical signals to find insects, store them behind their bill, come up and then eat them. It uses electrolocation – sees using electricity – Like bats use echolocation.

Under their bill are about 40000 sensors arranged in longitudinal strips. These sensors can detect fluctuations in the surrounding electric field. Even something producing a very minor electric fluctuation at a distance – contractions in the muscles – can be detected by the Platypus.

Sharks do the same and this is the reason they attack and damage our internet cables under the sea.

Mechanical sensors:  Besides that 60000 mechanical sensors (push rods) are used to detect movement in the water. Scientists say that the information from the electrical sensors and mechanical sensors is combined by its brain to calculate the prey’s exact location.

No Nipples: The young ones feed on milk from the mother Platypus. This milk doesn’t come from nipples, it comes from modified sweat glands (not unique to platypus) under its body. It has no nipples.

They can eat their own body-weight in under a single day.

They find it hard to stay underwater because they have a natural buoyancy. Yet, they can use other objects to stay under water for a maximum of 10 minutes. Then they have to come up for air.

Babies: The baby Platypus does not have an official name. Some call it puggle (which is not correct). But the accepted word, “Platypup” can be used.

Plasma Speakers

by Anupum Pant

Not many would have heard of speakers other than those which use magnetic materials to produce sound. But if you still haven’t heard about Plasma speakers or ionic plasma tweeters, you are really missing something great. Read on for more.

About Plasma Speakers

I talked about sound a few days back and mentioned that it is something that propagates through a medium due to pressure changes. Normally, magnetic speakers create these pressure waves by moving a diaphragm with the help of a varying magnetic field. But, plasma speakers do this by varying the air pressure through a high energy electric arc. This arc is produced by ionizing the gas present in between two terminals (ionizing reduces the electrical resistance of air which creates a visible arc).

These speakers use an extremely high energy arc which also increases the temperature of surrounding volume of gas to very high levels. So, before learning anything about them, the first thing you have to know is that these seemingly harmless things can kill you.

The Dangers

Plasma speakers are not toys. Old men, people with heart problems, kids etc should stay away from them. Even if an adult is handling them, they need to be informed about what they are doing first. It is better to have someone close who knows well, how these things work. Although the commercially available speakers are fairly safe, DIY kits can prove to be fatal. The kind of dangers involved with these devices:

1. The electric discharge – Think of it as a lightning. The dangerous high voltage device has the potential to kill you, if any of your body part comes close. Keep all bodily parts away.

2. Gas danger – The constant supply of ozone used for this project can actually be much more dangerous than the electric arc. Ozone used in this project, silently increases in concentration which can be fatal. It is important to keep the room well ventilated.

A few more things about them

Invented by WIlliam Duddells in the year 1900 these are not speakers, but tweeters. That means, that there will be no window cracking bass that is going to come out of them. Unlike magnetic diaphragms, the arcs have no weight and are able to produce a very crystal clear sound by moving back and forth very quickly. See the video below.

They work by changing temperature inside the gas chamber which makes them go red to purple as the frequencies of a song change. However, an un-modulated arc will just produce noise, something like you hear at first in the video. Also, they need a constant supply of Helium and Ozone coming into the chamber. These gases get ionized inside to produce the arc.

[Read this for more history]

Where can I get them?

In 1970 Magnat used to produce them, but they no longer produce plasma speakers now. The point is, they were the pioneers in bringing this to the masses.
Acapella sells them for an eye-popping price of 23000$. These costly ones are revered for their sound quality.
Other DIY kit can be bought for as low as 100$ [here]
Build one on your own for cheaper. (if you are willing to risk your life) [tutorial here]