Is it possible measure simultaneously square of angular momentum and its x projection ( ^L2 and ^Lx )?Why? Proof.
Question
Is it possible measure simultaneously square of angular momentum and its x projection ( ^L2 and ^Lx )?Why? Proof.
Solution
Yes, it is possible to simultaneously measure the square of the angular momentum and its x projection. This is because the operators corresponding to these two quantities commute, meaning that the order in which they are applied does not affect the result.
In quantum mechanics, the commutation relation between two operators A and B is given by [A, B] = AB - BA. If this commutation relation equals zero, the two operators are said to commute and the physical quantities they represent can be simultaneously measured.
The operators for the square of the angular momentum (^L2) and its x projection (^Lx) are given by:
^L2 = ^Lx^2 + ^Ly^2 + ^Lz^2 ^Lx = ^Lx
The commutation relation between ^L2 and ^Lx is then:
[^L2, ^Lx] = [^Lx^2 + ^Ly^2 + ^Lz^2, ^Lx] = [^Lx^2, ^Lx] + [^Ly^2, ^Lx] + [^Lz^2, ^Lx]
Since ^Lx commutes with itself, [^Lx^2, ^Lx] = 0. The other two terms, [^Ly^2, ^Lx] and [^Lz^2, ^Lx], also equal zero because the components of angular momentum in different directions commute.
Therefore, [^L2, ^Lx] = 0, meaning that the square of the angular momentum and its x projection can be simultaneously measured.
Similar Questions
What is the commutation relationship between the total angular momentum operator L2 and any of its components, e.g., Lx?OPTIONS [L2,Lx]= -iℏLx [L2,Lx]=0 [L2,Lx]= iℏLx [L2,Lx]= ℏ
How can the angle between the angular momentum vector ⃗ L and the z-axis be calculated in quantum me-chanics? Calculate the allowed possible values of this angle for 2p - orbital.
When the commutation relationship [Lx, Ly] = iℏLz true, what does it imply about the simultaneous measurement of Lx and Ly?OPTIONS Lx and Ly cannot be measured simultaneously with certainty. Lx and Ly are compatible observables. The product of the uncertainties in Lx and Ly is zero. The product of the uncertainties in Lx and Ly is ℏ.
Which of the following type of perspective projection is also called “Angular Perspective”? A. Three-point B. Two-point C. Four-Point D. One-point
Angular momentum is minimum when the angle between position vector and linear momentum is ..... degree
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.