Originally posted by chunyong:
don't listen to those people trying to scare u. they donno science and physics, dats why anyhow say. i will use physics to explain why won't pregnant.
to get her pregnant, u need ur sperm to unite with AT LEAST one of her egg. Since the egg is not located at or near the labia region, it is not possible for your sperm to hit the egg. Even if the small drop of clear liquid dat is produced sub-consciously during the process, if u didn't shoot, it won't have the energy to propel itself further into the shaft cos it needs work to be applied to it for it to move. newton's law states 'object at rest remain at rest', therefore, it will remain where it is and will even slide out due to force of gravity when the gal is standing up, assuming frictional force to be much lesser than MA, where M=mass of sperm and A = 9.81m/s*s, therefore putting frictional force to be 0.
if the gal is lying on the bed for a long time, the sperm will slide until frictional force - Ma >0 where a is the acceleration along shaft. since newton's law also states 'for every force, there exist an equal and opposite reaction force', therefore this further proves that the displacement of the sperm when the gal is lying down tends to zero as total net force is 0.
Assumptions made
1) We take the shaft as an isolated system with no external forces, heat or vibrations.
2) The shaft is not moving
3) Frictional force remains the same as the initial stage throughout.
4) No further lubrication occurs during the experiment.
your knowledge on the human anatomy is somewhat flawed. Sperms have a flagellum for movement. the seminal fluid produced by the prostate gland will provide the sperms cells with nutrients and give them energy for respiration to occur. Energy released during respiration will enable the sperm to move its flagellum(tail) and allow it to "swim",usually upwards. According to the menstrual cycle, A girls most fertile days will be the day when the uterus lining is thick and spongy. This is the preparation for implantation to take place. An egg from the ovule is released around this time(when the uterus lining is thick and spongy). When the sperms swim upwards to the fallopian tubes and meets an egg, chances of fertilisation is very high. But the seminal fluid(transparent liquid ejaculated by the penis) does not contain the bulk of the man's sperm. As such, if you are lucky enough to pull away from the vagina while you are petting your gf, most of the sperms would not be able to enter the vagina. So chances are not very high that fertilisation will take place. BUT THERE IS STILL A CHANCE AS SPERMS CAN SURVIVE FOR AT LEAST 3 DAYS IN THE FALLOPIAN TUBES!!!! Next time, Use a condom AND apply spermicides on it to ensure that the chances of pregnancy are less than 1%.
Btw , you do not need gravity or external force for the sperms to swim upwards. The sperm is a living organism. It has a flagellum for movement and it moves in a random direction, this explains why Millions of sperms must be ejaculated, so that the chances of a sperm meeting an egg IN the fallopian tubes is higher.
