📚 Learning Guide
Energy and Uncertainty in Quantum Mechanics
medium

If a particle's position is precisely known, what is the most direct consequence on its momentum according to quantum mechanics?

Master this concept with our detailed explanation and step-by-step learning approach

Learning Path
Learning Path

Question & Answer
1
Understand Question
2
Review Options
3
Learn Explanation
4
Explore Topic

Choose the Best Answer

A

Its momentum becomes completely certain and predictable.

B

Its momentum becomes highly uncertain and difficult to measure.

C

Its momentum increases indefinitely.

D

Its momentum remains constant regardless of position.

Understanding the Answer

Let's break down why this is correct

Answer

If a particle’s position is known exactly, the uncertainty in its position Δx is essentially zero. According to the Heisenberg uncertainty principle, Δx Δp ≥ ħ/2, so when Δx approaches zero the product forces Δp to become very large. This means the particle’s momentum is completely uncertain, spanning an infinite range of possible values. For example, if you pinpoint a particle’s location to a single point on a screen, its momentum could be anything from negative to positive infinity, making it impossible to predict its motion. Thus, knowing a particle’s position precisely destroys any useful knowledge of its momentum.

Detailed Explanation

Knowing a particle's location very well means the rule that links position and momentum says the momentum values become spread out. Other options are incorrect because The idea that a precise position gives a definite momentum is a common mistake; The belief that a precise location makes the momentum grow infinitely is wrong.

Key Concepts

Heisenberg Uncertainty Principle
Momentum and Position Measurement
Quantum Mechanics Fundamentals
Topic

Energy and Uncertainty in Quantum Mechanics

Difficulty

medium level question

Cognitive Level

understand

Ready to Master More Topics?

Join thousands of students using Seekh's interactive learning platform to excel in their studies with personalized practice and detailed explanations.