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A particle can be in two different states given by orthonormal wavefunctions ψ1 and ψ2. If the probability of being in state ψ1 is 1/3, find out normalized wave function for the particle. |
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Answer» Answer: . The wavefunction of a particle confined to the x axis is ψ = e −x for x > 0 and ψ = e +x for x < 0. Normalize this wavefunction and calculate the probability of finding the particle between x = −1 and x = 1. Answer: Normalization refers to the requirement that Z ∞ −in f ty ψ ∗ψ dx = 1. If ψ does not satisfy this property, because it is a SOLUTION to the Schrodinger ¨ equation (SE), which is a linear equation, Nψ, where N is a constant, is also a solution to the SE. Ignoring the acceptability of the given function to be a wavefunction, we proceed to normalize the function. We look for a N, such that R Nψ ∗Nψ dx = 1. That is N 2 Z ∞ 0 e −x e −x dx + Z −∞ 0 e x e x dx = 1 Each of the INTEGRALS is a 1 2 so N2 = 1 or the wavefunction is normalized. The probability of finding the particle between x = −1 and x = 1 is obtained by integrating ψ ∗ψ over this domain. P = R 1 −1 ψ ∗ψ dx R ∞ −∞ ψ∗ψ dx In this instance, the denominator in the above expression is unity. The probability of finding the particle in the DESIRED region is P = Z 1 0 e −x e −x dx + Z −1 0 e x e x dx = 1 2 e 2 − e −2 |
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