DeBroglie vs. E= 1/2mv^2

[Kaleigh Olla 1L]

How do you know when to use the DeBroglie equation (lambda=ℎ/mv) instead of E= 1/2mv^2 when finding the velocity? For example, in question 14 on the achieve HW, I used the wavelength to find the energy and then used the energy to solve for speed in E= 1/2mv^2. Is this incorrect?

[Eszter Kovacs 1A]

Hi!

I think it might be easier to just use the de Broglie equation since you can calculate the speed from the momentum.

[Nandini_Parmar_1I]

Along with calculating the speed from momentum, it also helps with what information is given in the problem. Also remember that Plank's constant (h) is used to describe the behavior of particles and waves, and wavelength to relate speed whereas the other is more of an energy equation.

[Diya Kar]

What wavelength is considered no longer detectable as an electron with wavelike properties and rather one that exhibits particle like properties?