Those were well established as standard variables, as were x, y, and z. That makes Hamilton's decision to use "q" as a generalized position variable -- one that can represent either r or theta -- to be plausibly based on its lexical order and the fact that q just doesn't get used for anything in mechanics.
Choosing an adjacent letter for the conjugate variable makes sense just like x,y,z or Maxwell's use of triplets of letters to represent the three vector components of each field.
When was "p" first used to represent momentum in a physics textbook, and when did it first appear in an introductory level physics text book? This would be a good exercise for your students if they have never searched for something in a college library that has a vast collection of old books made of paper, particularly if your department has a collection of out-of-date textbooks that go back a century or more.
I believe the answer is circa , in the post-sputnik revolution in science education, but I have never looked beyond the fact that it does not appear in a physics book used at a large university circa or other old textbooks I have collected or read.
They use mv. Wide use of a symbol for momentum appears to be quite new. Momentum doesn't even get its own unit. I see that Hamilton used eta for the generalized position in his second essay linked from above and some strange character for the generalized momentum. He does, however, use p for the initial values of the generalized momentum see just below equation A on page 5 and the integrals that show up later in his treatment of perturbation theory.
So there is a hint of it in Hamilton's work, but since I don't even know if Lagrange used q for the generalized coordinate, maybe the answer IS in a textbook where someone else rewrote all of it in a consistent notation. By drorzel on May 18, Today's lecture topic was position-space and momentum-space representations of state vectors in quantum mechanics, which once again brought up one of the eternal questions in physics: Why do we use the symbol p to represent momentum?
History of Science. More like this. Which isn't to say that Hamilton didn't pick p and q deliberately, as they turn out later to be important, p,q, being easier to write I suppose As I say, I'm not entirely sure about the connection between Hamilton's original p,q in an optical system, and the p,q of the later Hamiltonian formalism.
OK, here is an explanation, totally unfettered by any inconvenient facts: Obvious symbol, "m", already used by mass which would make for a pretty silly-looking equation. I thought momentum was actually represented as rho. What about the cartoon that shows Einstein standing before a blackboard scratching his head? He's written E - m b2 and crossed that out. He's got the chalk in his hand and he's about to write the next equation and make history!
It certainly is not anywhere in Newton's work. The fact that "p" also appears in impulse and impetus probably sealed the deal for him. Why is the symbol for momentum in physics denoted by p, is it because all other letters are taken or that momentum starts with p in latin or what? Question Asked by j. Answer has 3 votes. Currently voted the best answer. I always thought that the p you are referring is actually 'rho' in greek alphabet and i think it was choosen at random.
Gnomon Answer has 2 votes. Gnomon 21 year member replies Answer has 2 votes. Momentum is commonly represented by the letter " p ".
I've never seen the greek letter rho used for momentum. The unit of momentum is the product of the units of mass and velocity. The formula for force says force is equal to mass m multiplied by acceleration a. Impulse applied to an object produces an equivalent vector change in its linear momentum, also in the same direction.
On the other hand, you can also say that the change in momentum is equal to the force multiplied by the time in which it was applied or the integral of force with respect to time, if the force is not constant over the time period. Answer- two factors affect the momentum, namely, the mass of the object and its velocity. Velocity , not speed, as the direction is an important part of momentum given that it is a vector quantity.
One of the most powerful laws in physics is the law of momentum conservation. For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. Kinetic energy must always be either zero or a positive value. While velocity can have a positive or negative value, velocity squared is always positive.
Kinetic energy is not a vector. Introductory Momentum Equations, Definition Momentum is a vector. We can use algebra to rearrange the momentum equation. MV , the abbreviation for megavolt, or 1,, volts, a measure of electrical potential.
Mendelevium, a chemical element with former symbol Mv. In science, force is the push or pull on an object with mass that causes it to change velocity to accelerate.
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