Uncertainty in the position of a particle, and momentum question

[Zit501]

Hi all,

I just can't wrap my head around this one. It should be fairly easy, but I'm lost!

Homework Statement

Suppose that the uncertainty in the position of a particle is of the order of its de Broglie wavelength. Show that in this case the uncertainty in its momentum is of the order of it's momentum.

Homework Equations

Not 100% sure...

Delta x is similar to the wavelength
Delta p is similar to Plancks constant over wavelength
Therefore delta x delta p are similar to Plancks constant

The Attempt at a Solution

Well I can see how delta x and delta p can be related together to the wavelength, but after that I'm lost.

Any help much appreciated! I'm a B.Sc Mechanical Engineer doing an entry level nuclear physics course and I'm holding on... just.

 

[CompuChip]

Yes, so you almost got it.

$$\Delta x \sim \lambda$$
If the uncertainty relation is near the minimum value, then
$$\Delta x \Delta p \sim \hbar$$

So what is $\Delta p$ then. What is $\lambda$ in terms of p?