### 1B.25

Posted: **Sun Oct 27, 2019 5:55 pm**

by **Kimberly Koo 2I**

I don't get how to solve this problem. It states that, "What is the minimum uncertainty in the speed of an electron confined within a lead atom of diameter 350. pm? Model the atom as a one dimensional box with a length equal to the diameter of the actual atom". Thank you

### Re: 1B.25

Posted: **Sun Oct 27, 2019 6:02 pm**

by **Jiyoon_Hwang_2I**

For the first part of the question you would use the formula Δp ≥ h/4πΔx. Plug in Planck's constant for h and 350*10^-12 m for Δx. After plugging in all of the values you should get an answer close to 1.51*10^-25 kg*m*s^-1. Then, use the formula Δv = Δp/m (this formula is derived from the equation p = mv). Plug in 1.51*10^-25 kg*m*s^-1 for Δp and the mass of an electron for m (9.1*10^-31 kg). You should get an answer of 1.65*10^5 m/s.