[Report This]Date: September 02 2013 5:01 PM Title: Chapter 9 Journey
I did some searching regarding what effect a lower gravity would have on water. What I've found seems to indicate that the "half displacement" assumption is wrong. Floating objects such as ships do indeed displace their own weight in water, and ships on Watatsumi weigh half of what they do on earth, but water on Watatsumi also weighs half of what it does on earth, so displacement shouldn't change. Or rather, it shouldn't change because of gravity. It turns out that if a ship is moved from salt water into fresh water (usually that happens by moving from a sea into a river) it will end up sitting slightly lower in the water. Fresh water is a little less dense than saltwater, so a ship in fresh water has to displace a greater volume to reach its own weight.
From what I've found, the only significant effect a lower gravity would have on water is that pressure doesn't increase with depth as much. That would make deep diving easier.
To be clear, I'm no physics expert; these are just the conclusions that I reached after some online searching. If I'm wrong, please don't hesitate to say so.
Author's Response:
Note; that was very helpful! So I find your help very wanted and needed. Though I researched a bit to substantiate your claims.
So in reality than they should really be slower if anything. But I still wonder because the water density should not change under different gravity?, it should just weigh less? In which case the ship would insert less force on the water and therefore sit higher? But this is an actual good question. I did a little more reading and determined Archimedes' principle should solve it, as water and the ship remain at a constant density, and the gravity is the only changing factor, then displacement should be acquirable with a bit of math.
Basically since. "Archimedes' principle states that the buoyant force experienced by a submerged object is equal to the weight of the liquid displaced by the object." The weight of the object is halved, so the amount it displaces should also be halved, resulting in the ship sitting higher, but this is in fact wrong, as you have stated. That is because the ship is still displacing an equal proportional amount of water to its mass, which never changes. Since the density or mass of fresh water is less then salt water, it should sit lower as you have said. In this case salt water weighs more than fresh water by 2.5%. This would mean that fresh water is 2.5% less dense then salt water. So The ship should displace an additional 2.5%. So if the Yamato for example displaces 72,000 long tons, in Watatsumi it will displace 36,000(1.025)=36,900 long tons.
Now as for higher speeds because the amount of force needed to move forward through water is less has been debunked. But in this case the force provided by the Kampon boilers to move 72000 tons now only needs to get 36,900 long tons moving against the water. In this case the ship should sit lower than on earth resulting in more drag, but Newton’s second law says that friction is what slows an object down. Friction is lowered if an object has less weight "which is calculated by the mass and gravity", while the Kampon boilers apply a force which is set to fight a higher force of friction on earth. This results in faster starting and higher sailing speeds, further because there is less water friction occurring, the time required to stop the ship at high speed according to Newton's second law is doubled. Basically the time it took to get to full speed on earth remains the same, accept now the fastest speed is higher. Here is a link in how Friction is generated. http://www.d123.org/olhms/ebarlos/documents/PSC03BAD.pdf But anyways basically the Yamato had a top speed of 27 knots, which should be doubled to 54 knots, with a 2.5% loss in speed due to fresh water. The destroyers could make 35 knots or 70 knots in Watatsumi. Given the facts.
This actually turned out to be good news faeriehunter, as I found out if Yamato had fired her main guns with less water displaced she would have capsized since she sat in the water higher.
Also Capillary action would be changed as well, especially in the case of surface tension but this additional force modifies only the amount of fluid displaced by the ships but that is already factored into to Archimedes formula.
Too bad no subs were in Operation Ten Go. They could indeed go deeper as the pressure under water would be less.
Thank you again for your continued support. And maybe just maybe this will be helpful to other writers.
[Report This]Date: August 31 2013 12:46 PM Title: Chapter 9 Journey
It sounds like the fleet is about to confront a King Kong-sized version of one of Maurice Sendak's Wild Things.
:-)
Author's Response:
That made me laugh. The big fuzzy wild things... Well, I can say the demon the fleet is now encountering is based on the Japanese myths and legends of the Oni. A large wild haired humanoid ogre with horns, a loincloth, and a giant kanabo. In Japanese myth they are large fearsome creatures, bringers of large catastrophes. Anyways for mine you will have to wait and see what their like.
Thanks for the review again.
On an unrelated note.
The problems I'm having now for upcoming chapters is physics related. I actually have a friend who's a studying particle physicist, but he didn't want to be bothered by my questions. lol Though I did find out that the ships should be faster due to their displacement being halved, Hydroplaning. As to how much the halved displacement gets the ships, he could not answer, so for now I'm using the need to save gas and prevent damage to the ships boilers as an excuse to stay within slower speeds. If someone could find the answer it would help me a lot. The weapons effectiveness, is actually consistent, but with less gravity they have twice the range and accuracy.
So I've recently been contemplating the math for some possible coming scenario's, so I guess this is sort of, and sort of isn't a spoiler, it's all hypothetical for what if scenario's.
Anyway my problems stems from the effectiveness of 130mm 50 caliber, 100 lbs casings effectiveness in a half gravity environment against a 4,800 ton giants flesh. I can't seem to find any good data sheets for WW2's Japanese Destroyer guns. "War secrets." Though I do know they were said to be able to penetrate four feet thick steel armor, if my sources are correct. Steel has a density of 7.8 g/cm3 while the average human body has 1.062 g/cm3. So the Penetration should be 7.34 times greater. But the rounds could penetrate that amount of armor and keep going, so it should actually keep going further than that.
So for a Giant I think, it should penetrate roughly thirty to forty feet. Now given his chest is anywhere between thirty to forty feet thick. And the bullet, or in this case ammo rounds from the naval guns are five inches. In perspective of a giant, that would make them appear to be one inch in diameter, almost twice the size as a standard bullet. So I believe they should be quite effective, if my math is right.
If nothing else the Yamato is armed with nine 18 inch guns with 3 ton beehive canister rounds which releases over 3,000 pieces of shrapnel in a cone like manner, similar to a shotgun. Oh and like 6, 6 inch guns, and 24 destroyer 5 inch guns.
Anyways if anyone has any thoughts on the matter of ballistics or sciences of the Ryujin world, please give me a hand with your knowledge. I know The Titan universe shares similarities to the Ryujins world, so maybe JohnnyScribe, or openhighhat might know some of this stuff already.
Date: August 31 2013 6:01 AM Title: Chapter 9 Journey
Apparently Shouta isn't the only one who can't think straight when sleep deprived. After Momo found out that Maki cared for Shouta so poorly that he suffered a heat stroke, I'd have expected her to transfer his care to someone else. She may not like him, but given Ryujin law it's in her best interests to do whatever is needed to ensure Shouta's safety. Instead Momo not only lets Maki keep him, she also sends Maki off alone to Otohime despite being warned that that is unsafe. With several of Otohime's guards present to witness all this.
I was wondering, under what circumstances does a Ryujin get executed for a man's death? I assume that it happens if the death is due to malice or negligence, and that nobody gets executed if the man died due to natural causes such as disease, but what about death by accident?
Also, am I correct in assuming that neither Maki nor Momo have told any of the other villagers about Shouta? I can't think of any other reason why his presence isn't the talk of the treetown.
Author's Response:
Momo definitely made a bad choice, but it was her choice to make. She's made a choice to remove her husband's stress, even if it's illogical to do so, jeopardizing her own safety. She was selfish and just didn't care, the fact she ignored Othime's guard shows this.
As for Ryujin law, your about spot on. Accidents fall under negligence sometimes, as well as some sickness. As man are a very rare and important commodity in society, the often are protected and surrounded by many woman.
Yes Shouta has remained a secret. Momo spent all her time consoling her husband, while Maki wanted to keep him secret for her own interests and slept.