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. J

    How does a collider know both the energy and position of the particle?

    Presumably a collider has some sort of pinhole out of which particles get ejected in a particular direction, and the energy (momentum) with which they are ejected is supposedly known. So, the operators/designs of the instrument know both the position (at the ejection pinhole, or whatever) and...
  2. M

    Velocity as a function of position problem (simple i think)

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  3. T

    Operators and the position representation

    I have a question about the formalism of quantum mechanics. For some operator A... \langle x |A|\psi\rangle = A\langle x | \psi \rangle Can this be derived by sticking identity operators in or is it more a definition/postulate. Thanks.
  4. S

    Position, Velocity, Acceleration, and Distance?

    Homework Statement The position of a ball moving on a straight line has an equation of p(t) = 1/3t^3 - 2t^2 +3t , where p is its position and s is time in seconds 1. At what times is the ball at rest? 2. Using its velocity and acceleration, determine the balls DIRECTION and if it is...
  5. Z

    Partial Derivatives of the Position and Velocity Vectors of a Particle

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  6. V

    Higher order time derivatives of position

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  7. D

    Write a program using Bisection method and method of false position.

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  8. fluidistic

    Eigenvalues of the position operator

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  9. M

    Position analysis of slider crank like mechanism using loop equations

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  10. A

    A Penny Falling of a Staionary/Fixed Position Sphere

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  11. U

    Finding the Minimum Speed of a Particle with Given Position Function

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  12. T

    How to find equation for a position vector function on a parabaloid?

    Homework Statement Velocity vector given by r'(t)=<cos(t), -sin(t), -2sin(t)> Surface that the position vector needs to lie on: z=x2+y2 Homework Equations Integral of r'(t) will give position function The Attempt at a Solution I know that the integral of r'(t) will give me...
  13. C

    Position of subshells in a bond

    I've learned that there are three types of p shells, namely Px, Py and Pz, each in a different direction. I've also learned that when different atoms bond together, they form specific shapes depending on the number of bonds and electrons. I want to ask, will the shape of the p or d subshells...
  14. D

    Curling simulation position functions

    The Canadian national men's curling competition (the Briar) is going on this weekend and I am motivated to write a computer program to simulate the motion of the rocks on the ice. I see on TV that the rectangular rink 14 by 126 feet appears to be trapezoidal on the screen, with the front about...
  15. E

    Differences in position in 2 very similar circumstances

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  16. H

    Global position and orientation of a point relative to another

    Hi there all, I have a personal project I'm working on and since I haven't done any linear algebra in many years I'm not sure what I think is right, is right. I'm also not entirely sure this is the right place to ask but I'm asking more for confirmation/clarification of methodology than...
  17. I

    Finding phi constant based on initial position and initial velocity

    x(t)=Acos(ωt+ϕ)\\ v(t)=-Aωsin(ωt+ϕ)\\ \\ Let\quad n=integer,\quad A=0.5,\quad ω=2.\\ \\ Given\quad initial\quad position\quad (0,\quad 0.25)\quad and\quad initial\quad velocity\quad (0,\quad 1),\quad find\quad ϕ.\\ \\ x(t)=0.5cos(2t+ϕ)\\ 0.25=0.5cos(ϕ)\\ ϕ=±1.0471975512+2πn\\ \\...
  18. R

    Questions about finding position, velocity, acceleration related

    A stone is thrown upward from the top of a 20 m high cliff at an angle of 25 degrees. The stone has an initial velocity of 15 m/s. Make the BASE of the cliff the origin. (a) Write out the position, velocity, and acceleration vectors for the stone. (b) What is the magnitude of the velocity of the...
  19. C

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  20. K

    Determining on what type of Motion to use on a Position Time Graph?

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  21. A

    Throttle Position sensor Working

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  22. A

    Calculate electric field at position x given ρ and thickness d?

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  23. J

    Particle in plane, find position vector

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  24. D

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  25. M

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  26. Astrum

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  27. Sneakatone

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  28. M

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  29. stripes

    Index of refraction, position dependent

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  30. B

    Brushless DC Rotor Position Question

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  31. C

    Position vector R of a particle moving x-y plane

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  32. N

    Noncommuting position variables due to quantum gravity

    I've read that if one wants to quantize gravity , there must be a smallest length scale " The Planck length " . If I want to measure the position of a point particle then in conventional Quantum mechanics I'll find it at the point $(x,y,z)$ at some-time $t$ with an arbitrary momentum but this...
  33. A

    Optics: Finding the wave equation given position and amplitude information

    A harmonic wave traveling in +x-direction has, at t = 0, a displacement of 13 units at x = 0 and a displacement of -7.5 units at x = 3λ/4. Write the equation for the wave at t = 0. Homework Equations The equation for a harmonic wave is r = asin(kx-vt+θ) a being the amplitude k...
  34. F

    Neutral wire position - Distribution system

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  35. L

    TISE in the position representation- basic question

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  36. D

    MHB Angular Velocity for Constant Separation Distance

    Determine the required angular velocity $\omega$ of the relative position vector in order to maintain a constant separation distance $r_0$ for two equal masses. What equations are needed for this?
  37. J

    Matrix Mechanics position and momentum operator

    Homework Statement Stationary states are related by 1/m*pij = Ei-Ej/(i*hbar) *xij where pij = ∫ψi(x)*p*ψj (x) and similarly for xij Homework Equations Classical correspondence for equation of motion is d<x>/t = <p>/m Schrodinger equation Ehrenfest Theorem Fourier Transform The...
  38. W

    Finding the position directly behind a player

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  39. M

    QM Interpretation & Young's Exp: Electron Position Defined?

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  40. S

    Expectation of Position of a Harmonic Oscillator

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  41. D

    MHB Position of Particle in a Circular Path: Solution

    Relatively easy question but I haven't done anything like this in awhile. $$ \mathbf{r}(t) = \hat{\mathbf{x}}R\cos(\omega t) + \hat{\mathbf{y}}R\sin(\omega t) $$ The particle moves in a circle so I want to show that the position is given by the above. I know at $t = 0$ the particle is on the...
  42. M

    Rate of Change Problem with Clock Hand Position

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  43. B

    What is the Curl of the Position Vector?

    Homework Statement compute the curl of: \vec{r} and \frac{\vec{r}}{r^3}Homework Equations \vec{r}=x\hat{x}+y\hat{y}+z\hat{z} r^3=(x^2+y^2+z^2)^\frac{3}{2} The Attempt at a Solution I figured out that the curl of \vec{r} = 0 as my book says it should be... however...I also need to prove...
  44. T

    Find time, given acceleration as a function of position.

    Hello guys, the following problem I've had is from Beer and Johnston, Dynamics: Homework Statement At a distance R above the Earth's surface, a particle at rest is let go. Given the gravitational acceleration: a =-g\frac{R^2}{r^2} where r is the distance from the center of the Earth to the...
  45. T

    Derive the following kinematics equation using the position and velocity equations

    Homework Statement { y }_{ f }={ y }_{ i }+{ v }_{ yi }t+\frac { 1 }{ 2 } { a }_{ y }{ t }^{ 2 }\\ { v }_{ yf }={ v }_{ yi }+{ a }_{ y }t Derive { { v }_{ yf } }^{ 2 }={ { v }_{ yi } }^{ 2 }+2{ a }_{ y }({ y }_{ f }-{ y }_{ i }) 2. The attempt at a solution This isn't an actual...
  46. M

    Energy vs. position eigenstates

    This might be a silly question, but I'm not sure about the answer... Commuting operators have identical eigenstates. For example: energy and position operators seem to commute: [E,x] = Ex - xE = 0 Does it mean that position and energy operators share identical eigenstates? Because...
  47. A

    Newton's third law in terms of inertial position vectors for n-body system

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  48. Arsenic&Lace

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  49. P

    Could I get a tenure track faculty position at a small liberal arts college or

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  50. H

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