Does Linear momentum operator and angular momentum operator

hellomister
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Homework Statement


Does Px Lx operators commute?

Homework Equations


This is just me wondering


The Attempt at a Solution


I tried doing this and I got something weird, my friend said that when you take a derviative with respect z or something that when you try to take the derivative of something that's not with respect to z it goes to 0. Is this true? p.s. I am not very good at math.
 
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You tell me. L_x is made up of rs and ps. Which r and ps is L_x made of, and which r and ps does p_x commute with?
 
\hat{\vec{L}} = \vec{r} \times \hat{\vec{p}}

\times is the cross product...

Do the math and then see if they commute

ps
[px , py] = [px , pz] = 0
 
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