Sup /tg/! I have a little question for the physics geeks among you. In a capes game I'm participating in there is a character that can steal all the kinetic energy of an object and release it through bursts of increased speed/strength. So how much kinetic energy would a loaded cargo ship (around 138,000 metric tons) have if it was traveling at around 40 kph? How fast would that temporarily make a 85 kg human move if released all at the same time, assuming super hero physics stops your cells from being crushed on an individual level?
Pic semi-related, The Flash's top speed.
>>47431138
You know, you could have just checked Wolfram Alpha for this, but the math isn't too bad so I'll do it anyway. KE=1/2mv^2. Standard units is to use kilograms and meters per second. So KE=(.5)(13800000)(23.333), or 1609977000 Joules. Translate that to an 85 kg human and they'll have a velocity of 6154.82 meters per second. That's about eighteen times the speed of sound.
>>47431329
Wait, shit, left out the exponentiation. And here I was going on about the math being simple, what a silly blunder. Okay, that's 37565593341 Joules, 29730.91 meters per second for an 85 kg human, or about 87.44 times the speed of sound.
>>47431368
Thanks! I'll be sure to notify the GM once this happens next session.
>>47431138
138000 metric tons = 1.38x10^8 kg
40 km/h = 40000m/h = 11.11.. m/s
KE = 1/2mv^2 = (.5)(1.38x10^8 kg)(11.11.. m/s)^2 = 8.518..x10^9 J
8.518..x10^9 J = (.5)(85kg)(v^2)
(v^2) = 200435729.8 m^2/s^2
v = 14157.53262 m/s (or 50967.11743 km/h if you prefer)
-t. someone who failed newtonian mechanics
>>47431368
well shit
>>47431329
Where did you get 23.333? 40 kph in meters per second is 11.1111, or 123.45679 when squared.
>>47431533
That's what I got.
>>47431368
>mfw someone in a game goes Mach 87
>>47431138
Do your superhero cells also let you not burn on top of supporting the kind of acceleration that lets you hit this kind of speed?
>>47431138
Using physics for this is dumb due to the amount of laws it would break, also the true value would be much different than the high school level newtonian 1/2mv^2 answer already posed in the thread
The real answer would require a differential equation using the 3D space that the ship was moving in, Bouyant force from the water, the the tidal force creating the waves, and many other minute details
A much more simple way to model the question would be to ask the dm the power output of the ship, you could take that as the energy you receive then using the Newtonian calculation to get the velocity of your hero, you could use a Lorentz transformation to be more exact because you will be in a measurable % of C
Now we get to the part where we break physics, if we assume that this energy transfer is perfect and instantaneous, and the hero has to use this energy to accelerate himself to kinetic potential velocity in a small amount of time then his cells are not going to need to be the only thing protected, the air around him will turn into a deadly plasma from extreme compression
TL:DR using physics to explain fantasy will end very badly
t.astrophysics major
Why doesn't the guy just steal the kinetic energy of the planet whenever he feels like? I'm sure just slowing the Earth's orbit by a fraction of a nanosecond would still be enough to blow a mountain to dust.
>>47436222
heck for that matter why doesn't he steal the energy from sunlight. I mean isn't light both matter and wave
>>47436222
Presumably there's some kind of limitation on how much he can steal at once, so the earth would be a constant battery but he could still only grab enough to move a ship around at any given moment
