Source: https://www.wired.com/2014/07/absurd-creature-of-the-week-pistol-shrimp/

Have you ever ordered shrimp-fried rice and wondered: “Could a shrimp actually fry this rice?”

Well, with a bit of physics we’re going to try to answer this age old question.

Nature has produced some bizarre ways for organisms to defend themselves or hunt for prey and one such evolutionary armament is the pistol shrimp’s enlarged claw that acts as one impressive bubble gun. The shrimp has two claws, one regular sized one for grabbing things and general motor functions and one very enlarged one. This enlarged one has an immobile lower half and a mobile upper half. When the shrimp wants to attack, it raises the upper half to be perpendicular to the lower half.

Source: https://phys.org/news/2018-01-million-years.html

A large amount of tension is now upon the upper half and when released, it slams down onto the lower half, generating a cavity within the water. This can lead to a pressure difference of about 80kPa[1]. The force that is generated from the cavity collapse is used to stun and injure prey. This is where the pistol shrimp gets it’s name from, it basically shoots high impact bubbles. These bubbles tend to go about 4cm and last only about a millisecond[1]. They even produce light.

Source: https://www.quora.com/Is-the-pistol-shrimp-hotter-than-the-sun

Source: https://iopscience.iop.org/article/10.1088/1755-1315/310/5/052057/pdf

Now that you’ve witnessed the power of the shrimp, let’s theorise if this shrimp could indeed fry rice.

According to [2], rice has a specific heat capacity of 782 J/kg.°C. At home, I would cook my rice in boiling water at 100°C. For the simplicity of this article, I will consider the shrimp is in a tank of water and not frying oil so that I can use the rice specific heat capacity which means the rice will be boiled and not fried.  If a shrimp were to be living in a tank in my house, room temperature would be  roughly 25°C so we need to raise the temperature of the rice by 100-25 = 75°C. According to [3], to serve 4 people requires 4 cups of rice. I am a selfish person and would like to be the only one to have genuine shrimp cooked rice so only 1 cup will be used which is roughly 225g or 0.225kg. All we need to know now is how much energy the shrimp dissipates into the water when the cavity it produces collapses. We will use a simple W=Fxd where F=PxA. The shrimp produces a bubble of radius usually 0.1mm or 0.0001m so the area of a circle would be pi x 0.0001^2=3.14e-8 m^2. F=80000 x 3.14e-8=2.152e-3N(e=x10^). With a distance of 4cm or 0.04m, we have 1e-4J. Not overly impressive but most of the energy is converted to sound. Now to find how many shrimps would need to click on our rice to cook it. Using the heat capacity from before, 782 x 75 x 0.225=13196J. Dividing that by 1e-4 would require us to have 1.32e8 pistol shrimps in our tank to simultaneously descend upon our rice and click with their claw to cook it, that’s about 132 million shrimp. This is a lot of shrimp and would probably get us into trouble with wildlife conservation organisations if we were to try this experiment. However, if the clicks last only a millisecond, that means you’ve just gotten the world record for fastest time to cook rice, much faster than the minute rice found in the shops.

So, what did we learn? Pistol shrimps have used physics to arm themselves with a powerful tool to conquer their own corner of the animal kingdom and also, if you have a little bit of hope in your heart and over 100 million shrimp, you too can have shrimp fried rice. Thanks for reading.

Source: https://knowyourmeme.com/photos/2358627-youre-telling-me-a-shrimp-fried-this-rice

[1]: https://iopscience.iop.org/article/10.1088/1755-1315/310/5/052057/pdf

[2]:https://www.ijarset.com/upload/2018/july/5-IJARSET-Bekkulov.pdf

[3]:https://www.averiecooks.com/easy-better-takeout-shrimp-fried-rice/

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