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### Uncertainty Question

Posted: **Sun Oct 13, 2019 11:05 pm**

by **DHavo_1E**

Hello,

Can someone explain why uncertainty is negligible in bigger masses, and more important with smaller masses?

### Re: Uncertainty Question

Posted: **Sun Oct 13, 2019 11:18 pm**

by **Julie_Reyes1B**

Hi!

The reason why the uncertainty principle is only significant with smaller objects is similar to why the de Broglie equation only yields noticeable results for smaller objects. Both equations involve a particle’s wavelike properties, which really only applies to subatomic particles. Dr. Lavelle’s lecture on Friday had a really great example which showed that a car would not have a noticeable wavelength/wavelike properties. Similarly, the uncertainty principle is built upon the principles of particle-wave duality, which we can’t apply to larger objects.

Hope this helps!

### Re: Uncertainty Question

Posted: **Mon Oct 14, 2019 1:18 pm**

by **Petrina Kan 2I**

In Dr. Lavelle's lecture today (Monday), he showed a great example of a baseball being hit by photons and continuing on its pathway and then compared it to an electron going through the same thing. Since the mass of the baseball is so large, it has little to no uncertainty and effect in its velocity and pathway when hit by a photon, which is why the uncertainty is negligible. However, since an electron has such a small mass its path is affected when it interacts with the photon, which causes the uncertainty in its mass and pathway. Hope this helps!

### Re: Uncertainty Question

Posted: **Tue Oct 15, 2019 11:26 am**

by **Anokhi Patel 2B**

In the example in lecture, the answer 3.4 x 10-10 m.s-1 was an unrealistic number for the uncertainty, since it was larger than the speed of light. How do we know when the velocity is an unrealistic number, will a probable speed always have to be lesser than 3.0 x 10-8?

Thank you.