It Takes 2.99 Gigajoules To Vaporize a Human Body

Have you ever wondered how much energy is needed to power a phaser set to kill? A trio of researchers at the University of Leicester did, so they ran some tests and found out it would take roughly 2.99 GJ to vaporize an average-sized adult human body. Quoting: "First, consider the true vaporization – the complete separation of all atoms within a molecule – of water. With a simple molecular structure containing an oxygen atom bonded to two hydrogen atoms, it takes serious energy to break these bonds. In fact, it takes 460 kilojoules of energy to break just one mole of oxygen-hydrogen bonds — around the same energy that a 2,000-pound car going 70 miles per hour on the highway has in potential. And that's just 18 grams of water! So as you can see, it would take a gargantuan amount of energy to separate all the atoms in even a small glass of water — especially if that glass of water is your analog for a person. The human body is a bit more complicated than a glass of water, but it still vaporizes like one. And thanks to our spies spread across scientific organizations, we now have the energy required to turn a human into an atomic soup, to break all the atomic bonds in a body. According to the captured study, it takes around three gigajoules of death-ray to entirely vaporize a person — enough to completely melt 5,000 pounds of steel or simulate a lightning bolt."

Comments

Vaporize or ionize?

[swamp_ig]

Hang on a moment... TFA isn't talking about vaporizing - turning water to steam. It's talking about ionizing, which is clearly going to require a much bigger quantity of energy.

For actual vaporization, making a very rough calculation - 60kg person, 2,270 kJ/kg latent heat of vaporization of water = 136 MJ,
Sure there's specific heat to add in there too, but the vaporization of water is the dominant term, so it's at least out by an order of magnitude.

Lesson learned - don't try and be 'all sciency' and use the wrong jargon!

Re:well done

[s13g3]

Leicester is correctly pronounced "lay-ses-ter".

No it isn't. It's pronounced "les-ter".

Source: I've been there. Also, this.