Question

The Principle of Uncertainty was introduced by:

• A. Broglie
• B. Avogadro
• C. Heisenberg
• D. Einstein

Hint:

Heisenberg's Uncertainty Principle is fundamental in quantum mechanics, establishing the limit on the precision of simultaneous measurements of certain pairs of properties, like position and momentum.

Answer 1

The Correct Option is C

Step 1: Concept.
The uncertainty principle states that the uncertainty in position multiplied by the uncertainty in momentum is greater than or equal to Planck's constant divided by four pi, meaning position and momentum cannot both be measured with unlimited precision at once.

Step 2: Match the name.
This relation is credited to Werner Heisenberg from 1927, and is different from de Broglie's wavelength relation, Avogadro's gas law, or Einstein's photoelectric equation.

Step 3: Final Answer.
The principle of uncertainty was introduced by Heisenberg.

Answer 2

Thinking about the specific question each scientist was trying to answer also separates them clearly.

1. Broglie: He was answering the question, can matter behave like a wave. His answer was yes, and it led to the concept of matter waves, not to any statement about measurement limits.
2. Avogadro: He was answering the question, how does the volume of a gas relate to the number of molecules in it. This has nothing to do with measuring position or momentum.
3. Einstein: He was answering the question, why does light knock electrons out of a metal surface. His explanation, that light comes in energy packets called photons, does not touch on any inherent measurement limit either.
4. Heisenberg: He was answering the question, can we know a particle's exact position and exact momentum at the same time. His answer was no, there is a fundamental limit, and that answer is precisely the uncertainty principle.

Of these four questions, only Heisenberg's is about a built-in limit on simultaneously knowing two properties of a particle, which is what the uncertainty principle is.

So the correct answer is Heisenberg.