Q. What is Heisenberg's uncertainty principle? Write the three forms of uncertainty relations. 

Ans.

The principle of uncertainty was described by Heisenberg in 1927. According to this principle "it is impossible to determine simultaneously the position and momentum of the particle with any desired accuracy." i.e. we can measure either the position or the momentum of a particle within the limits of experimental equipment. If we design, an ideal experiment to measure simultaneously the position x and momentum p of a particle there will be and an uncertainty in the position and an uncertainty in the momentum found such that

(1)  Time energy Uncertainty Principle

If the uncertainty in the measurement of energy is for the time then according to uncertainty principle.

(2)  Angular Momentum and Angular Position Uncertainty

If the angular moment of an object has an uncertainty J, the other quantity which is uncertain is the angular position q.