Ben W. answered • 12/09/19
PhD Python & chemistry tutor
An object with mass m, moving at speed u has an associated wavelength described by the de Broglie wavelength equation λ = h/mu where h is planck's constant (6.626 x10^-34 Js).
Be careful with units in this problem! Mass should be in kg and speed in m/s. For a muon (a subatomic particle with a mass of 1.884 × 10–25 g) traveling at 305.0 m/s, we can solve this using the de Broglie wavelength equation as follows:
λ = h/mv = (6.626 x 10^-34)/(1.884 x 10^-28 kg x 305.0 m/s) = 1.153 × 10-8 m or 11.53 nm
In order for the units to work out, recall that 1 J= kg·m2·s-2
The other problems are solved in a similar fashion taking note of the appropriate units.
Ben W.
It sounds like you're on the right track. Show me how you worked the problem including the actual values and I will try to help.12/09/19
Daisy G.
wavelength = h / m v wavelength = (6.626 x 10^-34) / (9.10 x 10^-28 g) x (3.85 x 10^6) = (6.626 x 10^-34) / (9.10 x 10^-31 kg) x (3.85 x 10^6) = (6.626 x 10^-34) / (3.503 x 10^-24) = 1.8915 x 10^-58 m = (1.8915 x 10^-58)(1 x 10^9) (converting from m to nm) = 1.8915 x 10^-49 yet it is wrong, i believe that i am not supposed to have the answer in scientific notation12/09/19
Ben W.
There is a calculator error in your last step. (6.626 x 10^-34) / (3.503 x 10^-24) = 1.892 x 10^-10 m or 0.1892 nm12/09/19
Pierre-Line R.
That was very helpful. Thank you.11/02/22
Daisy G.
For problems 2-4 I am using the equation listed and making sure that I am aware of the units yet I am wrong.12/09/19