/sci/ - Science & Math

Kinetic energies that go in opposite directions destroy each other.

A body in orbit receives kinetic energy that is opposite what it received 1/2 orbital period prior.

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>>11054760
>>11054769
>>11054772

>>11054760
false, the thermal energy in earth’s current atmosphere (and generally the earth) that was gained during gravitational accretion is long gone and was negligible to begin with

>>11054769
no they don’t. in elastic collisions you simply get things bouncing off one another i.e. a transfer of kinetic energies that preserves kinetic energy, and even in inelastic collisions the kinetic energy gets transferred to some other type of energy (thermal, chemical, sound waves, etc)

>>11054772
not really. in circular orbits the gravitational force does no work and thus no energy changes happen. in parabolic orbits the orbiting body trades kinetic energy for gravitational potential energy, which is _sort_ of an energy transfer but not really unless you start thinking about virtual gravitons

>>11056550
>the gravitational force does no work
then how does the planet keep moving in different directions? you need energy to change direction. an orbit is a perpetual motion machine.

>in inelastic collisions the kinetic energy gets transferred to some other type of energy (thermal, chemical, sound waves, etc)
thermal energy comes from compression because of uneven contact, gravity acts uniformly on the entire body

>>11056568
>gravity acts uniformly on the entire body
Lmao, no it doesn't.
>https://en.wikipedia.org/wiki/Gravity_anomaly

>>11056577
a non-uniform body creates a non-uniform field, but the difference is so extremely tiny it doesn't matter.

>>11056568
>then how does the planet keep moving in different directions? you need energy to change direction. an orbit is a perpetual motion machine.
learn some high school physics bro. work=force DOT dx (the change in position) so a circular orbit does no work i.e transfers no energy. an analogy is if you have a ball on the end of a rod on a frictionless hinge. if you spin it, without friction it will keep spinning forever. this doesn’t mean the hinge transfers energy to the ball. the ball doesn’t heat up or anything

>>11056580
Large enough to measure.

>>11056597
a body in orbit constantly changes position

>>11056550
the heat of the atmosphere comes from adiabatic pressure. that pressure comes from gravity.

>>11056612
>a body in orbit constantly changes position
dude, you seriously need to learn some high school physics.

if the direction of motion is perpendicular to the force, no work is done. the body in circular orbit is moving, but perpendicular to the direction of what it is orbiting, so no work is ever done during that orbit even though a force is responsible for changing its linear trajectory. this is 11th grade shit in the US. are you some sort of homeschooler? wait no, let me guess, you are a 30yo /a/fag who failed high school physics and thinks trolling /sci/ with pseud shit is cool because /pol/ and /x/ told you?

>>11056712
>if the direction of motion is perpendicular to the force, no work is done.
this is pure cope. "work" doesn't exist. only forces exist.

>>11056715
>high school physics is
>pure cope

sigh. just, sigh, anon.

>>11056719
the concept has literally just been made up to say that a force has no energy because muh thermodymanics

>>11056738
no anon, work is a central concept in newtonian physics. not even poltards deny basic mechanics

>>11056794
it's not basic, it's made up.

>>11056887
[math] \vec{F} \ \dot{} \ dx [/math] is not made up. and high schoolers learn it in 11th grade. if you want to argue whether the concept of "work" is real or not then you need to try harder. like maybe try Quantum Field Theory

>>11056893
it is completely and utterly arbitrary and not based in any reality. it's not physics.

in reality, gravity adds energy to the system continuously. that energy remains in the system as momentum, but that energy is also continuously destroyed by opposite energy on the other side of the orbit.

>>11056908
i thought you were the one who said that
> only forces exist.

didn't you say that?

anyhow your argument is absolutely retarded, since you arbitrarily define "other side" where it is "destroyed" vs. the original side where it is, i guess, "created"?

if you argue that only forces exist, then we are in another line of argument where maybe something intelligent could happen. but saying that for a circular orbit, one thing happens on one side but another thing happens on the other side... this line of argumentation fails at explaining the "symmetry" of where we choose to pick "which side is which"

>>11056928
you can define sides in terms of axis, but axis are also arbitrary and don't really exist. you know what a direction is and what it means for a direction to be opposite another.

kinetic energy has a direction, opposite energies cancel

>>11056935
i think you just completely ignored my argument about how you are trying to "pick sides" on a system where everything has a manifest symmetry. circular orbits are circular, and there is no preferred axis on a circle unless you arbitrarily assign one. if you admit your assigning of an axis is arbitrary, then you should logically admit that whatever relies on your arbitrary assignment is probably wrong. nature is symmetrical and picking your preferred direction is probably wrong.

>>11056946
you don't need a preferred direction, you just need to understand what opposite directions are, a direction can be opposite another without having a preferred one
>nature is symmetrical
no

>>11056952
sounds like you got BTFO bro, and now your last hope at surviving is CP-symmetry violation

i will reiterate that you sound very strongly like a high-school-physics failure who is trying to troll /sci/ because some /pol/ anon convinced you "fuck science, fuck high school physics, that shit is wrong, high school physics is so wrong because muh politics" which means you are an anti-science troll

>>11056967
reality shows something completely different from science