Relative uncertainty in momentum for electron measured to de Broglie wavelength

[physstudent.4]

Homework Statement

Suppose you measured the x-component of position of an electron to an accuracy
matching it’s de Broglie wavelength, i.e., Δx = lambda/2. What is the relative
uncertainty in the electron’s x-component of momentum, Δp/p?

Homework Equations

ΔxΔp >= h(bar)/2

The Attempt at a Solution

I just wanted to clarify that relative uncertainty is Δp, not Δp/p. My professor writes these questions and is currently sick, so I feel like he may have not been thinking completely clearly... I am finding Δp, and not the ratio Δp/p? I am pretty sure I merely need Δp.

 

[Browne]

I'm pretty sure that your professor does want you to find what the relative uncertainty is (which is Δp/p).

The key to this problem is that Δx depends on p.

 

[physstudent.4]

ooh, okay, I got it now, thanks!