Question

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求解
為什麼動量不需要代速度值？🤔

6.51 Using Heisenberg's uncertainty principle, calculate the uncer-
tainty in the position of (a) a 1.50-mg mosquito moving at a
speed of 1.40 m/s if the speed is known to within £0.01 m/s;
(b) a proton moving at a speed of (5.00 + 0.01) X 104 m/s.
(The mass of a proton is given in the table of fundamental
constants in the inside cover of the text.)
(a) Ax >= h bar /24p = 6.626*10-34/(1.5*10-6*0.01)/41 = 4/41*10-27 m
(b) Ax >= h bar/24p = 6.626*10-34/(1.67*10-27*0.01)/41 = 3/41*10-10 m
*

Answer 1

我不認識莫非

要先確定是否需要使用相對論
若不用相對論，動量就直接代p=mv
題目提到利用不確定原則，所以需要代的是差距值而不是定值，因為不確定原則只能計算出某個範圍（差距值），無法直接算出定值
如果能算出定值，就不會有電子雲的概念了