Question

Assertion :Heisenberg's uncertainity principle is contradictory to Bohr's theory. Reason: The Heisenberg's uncertainty principle states that we can never simultaneously know the exact position and the exact speed of an object. Because everything in the universe behaves like both a particle and a wave at the same time

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

In order to locate the position of an electron in an orbit accurately, a radiation of high energy has to be incident on it. This is because the wavelength of light falling on the object should match with the wavelength of the electron which is a microparticle.

Electron being a microparticle has very short wavelength and such short wavelength radiation has high energy. Such high energy radiation when incident on the electron, its velocity increases drastically. Thus certainty in position brings uncertainty in velocity.Thus, this uncertainty principle is contradictory to Bohr's theory of stationary orbits.

This principle is not valid for larger objects as the incident radiation would have very large wavelength and very less energy. Hence, the radiation cannot bring about much change in the velocity of the electron. Therefore both can be determined accurately and simultaneously.