Aman walks at1m/s, known to within an uncertainty (unrealistically small) of1μm/h.

(a) Compare the minimum uncertainty in his position to his actual physical dimension in his direction of motion 25cm,from front to back.

(b) Is it sensible to apply the uncertainty principle to the man?

Short Answer

Expert verified
  1. Δx~10-26×25cm
  2. No

Step by step solution

01

 Uncertainty Principle

The position and speed of particles (like electron and photon) is not known with perfect accuracy. This is the principle of Uncertainty.

02

Given data

Man weight65kg

Speed1m/s

Uncertainty1μm/h

03

Step 3(a): Compare the minimum uncertainty in his direction of motion

Given the uncertainty in the velocityv, we need to figure out the position measurement(Δx)constraint.

ΔpΔxh2mΔvΔxh265kg×10- 63600m/s×Δx≥1.054×10- 34kg×m2s2Δx≥1.054×10-34m2×1.81×10- 8Δx≥2.91×10- 27mΔx~10-26×25cm

Hence the solution is Δx~10-26×25cm

04

Step 4(b):Find whether uncertainty principle is applicable to man

The ambiguity in position is around 10- 26 orders of magnitude smaller than the man's width. Beyond the experimental observations, this is a very small value; therefore applying the uncertainty relation is pointless. The answer is No,it is not sensible to apply the uncertainty principle to the man.

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