Question

Identify the statement which best define the uncertainty principle?

• A. We cannot know for certain when any given radioactive particle will undergo decay
• B. We cannot know both the momentum and the position of a particle at the same time
• C. The laws of physics are the same in all intertial reference frames
• D. Light exhibits both wave and particle properties
• E. An unobserved particle can be in two places at the same time

Answer 1

The correct option is B We cannot know both the momentum and the position of a particle at the same time

Heisenberg uncertainty principle states that it is impossible to know the exact momentum and the exact position of particle at the same instant.

If we precise the value of position of the particle, then there will be large uncertainty in the value of its velocity (momentum) and vice-versa.

According to uncertainty principle, $\Delta p.\Delta x\ge \frac{h}{4\pi }$