What is Position: Definition and 1000 Discussions

The missionary position or man-on-top position is a sex position in which, generally, a woman lies on her back and a man lies on top of her while they face each other and engage in vaginal intercourse. The position may also be used for other sexual activity, such as anal sex. It is commonly associated with heterosexual sexual activity, but is also used by same-sex couples.The missionary position is the most common sex position, but is not regarded as the most favoured one. It may involve sexual penetration or non-penetrative sex (for example, intercrural sex), and its penile-vaginal aspect is an example of ventro-ventral (front-to-front) reproductive activity. Variations of the position allow varying degrees of clitoral stimulation, depth of penetration, participation on the part of the woman, and the likelihood and speed of orgasm.
The missionary position is often preferred by couples who enjoy the romantic aspects of ample skin-to-skin contact and opportunities to look into each other's eyes and kiss and caress each other. The position is also believed to be a good position for reproduction. During sexual activity, the missionary position allows the man to control the rhythm and depth of pelvic thrusting. It is also possible for the woman to thrust against him by moving her hips or pushing her feet against the bed, or squeeze him closer with her arms or legs. The position is less suitable for late stages of pregnancy, or when it is desired for the woman to have greater control over rhythm and depth of penetration.

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  1. R

    Orbital simulation - Calculate object position over time in a 2d plane

    Hi Im busy creating an application to simulation a rocket in orbit. I am having trouble as the results I am getting are incorrect. Could someone please check if I am using the correct method as stated below. Everything works on a 2d plane, and has a x and y coordinate and a x and y...
  2. E

    Normalizing a wave function and calculating probability of position

    Forgive me if this goes in elementary physics, but I think since it's an upper level undergrad class Homework Statement A state of a particle bounded by infinite potential walls at x=0 and x=L is described by a wave function \psi = 1\phi_1 + 2\phi_2 where \phi_i are the stationary states. a)...
  3. J

    Derive conservation of center of mass position

    Hello there, If a mass, m, is placed at one end of an boat of mass M, which is located on a frictionless ocean. If the mass, m, is moved from one end of the boat to the other end, conservation of center of mass position ensures that the boat shifts a small distance in the opposite direction...
  4. JonnyMaddox

    Lagrangian/Hamiltonian problems and find the position

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  5. D

    Position of spot in oscilloscope

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  6. A

    Calculate how far the spring is stretched from its position?

    A 7.5kg block is suspended at rest from a spring (k=45N/m) along a incline as shown below (where theta= 17°)
  7. U

    OPTICS: finding image position using matrix methods

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  8. T

    How to find the at rest position of a particle when trig functions

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  9. atyy

    Joint distribution of position and momentum

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  10. C

    Finding velocity as a function of position, constant acceleration

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  11. V

    Calculate the z position of the particle as a function of time.

    1. A particle of mass m is suspended from the ceiling by a spring with constant K and relaxed length initial lo, whose mass is negligible. The particle is released at rest with the spring relaxed. Taking the Oz axis directed vertically downward, with the origin on the roof, calculate the z...
  12. B

    Stern Gerlach and Position Measurements

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  13. 7

    Regarding r and sign convention for Position vectors for moments

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  14. B

    What Are the Steps to Analyzing a Position vs Time Graph?

    Homework Statement Position vs Time graph is given. It is a perfect parabola. So it has a quadratic equation Y: Ax^2+Bx+C that fits it perfectly. (a) Determine acceleration, initial velocity, initial position (b) Sketch a motion map (c) Sketch a v vs t graph My attempt: initial...
  15. S

    Position variables in the wave function

    I would like some clarification as to the mathematical and physical definitions of the position variables in the wave function. I often see that it is treated as a variable independent of time; this is utilized in the separation of variables technique. However, the Schrodinger equation implies...
  16. C

    MHB Change of Position: Word Question

    In a game of tug of war, your team changes -1 and 3/10 (-1.3) feet in position every 10 seconds. What is your change in position after 30 seconds? I said -3.9 but apparently was wrong. What am I missing? Thanks!
  17. M

    Find eccentricity of orbit given position and velocity

    Homework Statement Hey, I need to find whether an asteroid is in a "bound orbit" around the Sun. Furthermore, describe the shape of the orbit (elliptical or circular). The only information I have been given is its velocity and position at a random point. v_o=61m/s r_o=13.75AU=2.06E12m I also...
  18. Philosophaie

    Transform from one position to another.

    Homework Statement Using the Schwarzschild Metric and the Contravariant Position Vector 1x4 ##x^k## with 4 vector: $$x^{k'} = \left[ \begin {array}{c}r \\ \theta \\ \phi \\ t \end {array} \right]$$ where ##x^1## = r = 1 per unit distance ##x^2## = ##\theta## = 50 Degrees ##x^3##...
  19. C

    Temperature is inversely proportional to position away from center

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  20. D

    Charged particle final position equation

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  21. N

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  22. J

    How position of quarks decide the type of elementey particles ?

    I red the book halliday resnick I come to know protons and other such elementry particles are composed of further subparticles called quarks also that these quarks decide rather its proton or antiproton as if the arrangement of quarks are like 2up quarks up and 1down quark down then...
  23. Ascendant78

    Potential energy vs position graph w/ total mech. energy?

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  24. S

    How to find PhD position in my special situation?

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  25. S

    Expectation value for a position measurement

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  26. N

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  27. H

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  28. N

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  29. P

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  30. KiNGGeexD

    Find velocity as a function of position x

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  31. KiNGGeexD

    Velocity as a function of position x

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  32. T

    Trying to triangulate position of rogue radio transmitter.

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  33. atyy

    Must position be continuous in Bohmian mechanics?

    Here I'm thinking of a single free particle obeying the Schroedinger equation. The ensemble refers to multiple experiments with a single particle in which the initial wave function is the same. If I naively imagine that there is such a thing as a wave function that is delta function, in...
  34. lonewolf219

    Derivatives and equilibrium position of a spring

    I determined the equilibrium point of a spring by setting the potential energy function U(r) equal to zero and solving for r. But I just looked at the guided solution, and they took the derivative of U(r) first, then solved for r. Is my approach correct? Can we solve for the equilibrium...
  35. U

    Prediction of electron position

    Hi, I am working on a problem where my goal is to predict the location of pedestrians with certain constraints. So I have equations for the pedestrian motion (using social forces model) which is based on the idea of pedestrians movements are based on the forces acting upon them. For example, if...
  36. R

    Find an equation for position vs time given potential vs position?

    Homework Statement If I was given the potential energy equation U(x)=4x^2 How would I find the equation for position vs time? I know the graph for position vs time for this equation is a sin curve because the book tells me so. v = 0 and x = 0 when t = 0 Homework Equations...
  37. C

    What is the notation for the distance between two position vectors?

    If I have two 3 dimensional position vectors: s and v What is the notation for the distance between them? I know to calculate the distance I would use: r = SQRT ( (s1-v1)^2 + (s2-v2)^2 + (s3-v3)^2 ) where s1 is the first element in the position vector s etc. What is...
  38. C

    Numerically solving position and velocity of a particle

    I have derived a 2nd order differential equation for the position of a particle. I can turn it into a first order ODE by making it an equation for the velocity of a particle, which is easy to solve. Once I have the velocity (which is a large data vector), what is the best way to numerically get...
  39. R

    What Are Durable Alternatives to Potentiometers for Electronic Throttle Systems?

    Im currently designing a system to convert my cable pull throttle to an electronic one as part of a bigger project. Initially I was looking at using a potentiometer to indicate how far the acvelrator pedal had been pressed, but am wary of such a system due to the potential wearout. Can someone...
  40. E

    Determining How To Measure Position Langrange's Equation

    Figure 7.16 is a bird's-eye view of a smooth horizontal wire hoop that is forced to rotate at a fixed angular velocity co about a vertical axis through the point A. A bead of mass m is threaded on the hoop and is free to move around it, with its position specified by the angle \phi that it...
  41. T

    Various position functions from dx/dt

    Hi,I am just starting to solve calculus problems but,how is it possible,that from v(t) we can get so many differently position function.I mean,if we have v(t)=dx/dt we should always get just v=at+v0,and from this to get s(t)=1/2at^2+v0t+v0.But I have found many motion problems in which position...
  42. A

    Trouble predicting position equation on spring/mass damped system

    I am analysing a system that consists of a simple damper. The construction starts with a long compression spring; a small mass compresses the spring, and when released, the spring pushes the mass forward, until it hits a column of fluid. The mass has a controlled thru geometry, which allows...
  43. K

    Reactions at beam ends when varying load position - clearing doubts

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  44. E

    Finding The Position of A Mass As A Function of Time

    Homework Statement Consider a mass m on the end of a spring of force constant k and constrained to move along the horizontal x axis. If we place the origin at the spring’s equilibrium position, the potential energy is U = 1/2kx^2 At time t = 0 the mass is sitting at the origin and is given a...
  45. J

    Calculate position of the centre of a rigid bar

    Hello Everyone, I am working on building a simple robot. Basically, I have a small platform with two motorized wheels and rotary encoders on the edges. So, using the rotary encoders I can estimate the velocity of the two wheels. I then need to use this information to calculate the path...
  46. S

    What's the Difference Between a Position and a Position Vector?

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  47. D

    Triangle wavefunction - position uncertainty and probability amplitude

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  48. K

    Finding velocity and position from an acceleration vs time graph

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  49. 1

    Find position function of freefall with air resistence ODE

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  50. B

    How certain do we have to get about a particle's position ?

    i was reading brian cox's book about *the quantum universe * and he said something interesting if for instance we know that a particle exists in ΔX , then this delta has to be less than one wavelength * he did it with clocks * to know the probability of its existence somewhere else in the...
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