Wavefunction with specific values

AI Thread Summary
The discussion focuses on calculating the probability of locating a quanton based on its wavefunction values at two positions, xA and xB. The probability density is derived from the wavefunction, with Pr(xA) calculated as 0.09 and Pr(xB) as 0.0288. The ratio indicates that the quanton is approximately 3.125 times more likely to be found near xA than in a larger range around xB. Participants confirm the approach used to derive these probabilities is correct. The explanation of probability density in relation to the wavefunction is also clarified.
Gringema
Messages
6
Reaction score
0

Homework Statement


Near a certain position xA, a quanton's wavefunction ψ(xA)=-0.3 in some units. Near a certain position xB, a quanton's wavefunction ψ(xB[\SUB])=0.12 in the same units. If we do an experiment to locate the quanton, how many times more likely is i that the result is in a small range near xA than in a range twice as large near xB? Please explain.


Homework Equations


ψ(x)=ψ/sqrt(Δx)
|ψ|2=Pr(x)


The Attempt at a Solution


I used the definitions of wavefunction and amplitude to get Pr(x)=|ψ(x)|2Δx.
So Pr(xA)=(-0.3)2=0.09
And Pr(xB)=2(0.12)2=0.0288
Therefore Pr(xA)=3.125Pr(xB)

Is this the right way to think about this? And how would I "explain"?
 
Physics news on Phys.org
Gringema said:

Homework Statement


Near a certain position xA, a quanton's wavefunction ψ(xA)=-0.3 in some units. Near a certain position xB, a quanton's wavefunction ψ(xB[\SUB])=0.12 in the same units. If we do an experiment to locate the quanton, how many times more likely is i that the result is in a small range near xA than in a range twice as large near xB? Please explain.


Homework Equations


ψ(x)=ψ/sqrt(Δx)
|ψ|2=Pr(x)


The Attempt at a Solution


I used the definitions of wavefunction and amplitude to get Pr(x)=|ψ(x)|2Δx.
So Pr(xA)=(-0.3)2=0.09
And Pr(xB)=2(0.12)2=0.0288
Therefore Pr(xA)=3.125Pr(xB)

Is this the right way to think about this? And how would I "explain"?


|ψ(x)|^2 is the probability density of finding the particle around some specified x. So the probability that a particle is in a narrow range of width Δx around x is P = |ψ(x)|^2 Δx.
So P(xA) = Δx(-0.3)2=0.09 Δx and Pr(xB)=2Δx(0.12)2=0.0288 Δx, but you got the ratio correctly.

ehild
 
Last edited:
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top