/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q. 31 FIGURE P39.31 shows the wave fun... [FREE SOLUTION] | 91Ó°ÊÓ

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FIGURE P39.31 shows the wave function of a particle confined

between x = 0 nm and x = 1.0 nm. The wave function is zero

outside this region.

a. Determine the value of the constant c, as defined in the figure.

b. Draw a graph of the probability densityPx=ψx2

c. Draw a dot picture showing where the first 40 or 50 particles

might be found.

d. Calculate the probability of finding the particle in the interval

0nm≤x≤0.25nm.

Short Answer

Expert verified

a. The value of the constant c, as defined in the figure is 3nm-12.

c. The probability of finding the particle in the interval 0nm≤x≤0.25nmis 0.028.

Step by step solution

01

Part a Step 1: Introduction

Any wave function ψxshould satisfy the equation∫-∞∞ψx2=1...1

This equation states that the total area under the probability density curve must be 1.

Now, according to the question, wave function of a particle is confined between x = 0 nm and x = 1.0 nm

02

Determination of the value of the constant

Consider the interval, 0≤x≤0.75nm, the wave function can be written as,

ψx=43cx, xis in nm.

In the interval of 0.75nm≤x≤1nm, he wave function can be written as, ψx=4c1nm-x

Therefore, from equation 1, we can write,role="math" localid="1650896503981" ∫00.7543cx2dx+∫0.7514c1-x2dx=1∫00.7543cx2dx+∫0.75116c21-2x+x2dx=1169c2x3300.75+16c2x-2x22+x330.751=16.7527c2+16c23-5.25c2=10.25c2+0.0833c2=10.333c2=1c2=10.333c=3nm-12

Therefore, the constantchas a value of3nm-12

03

Part b Step 1: Probability density graph

Putting the value of c, we can write the probability density of the given wave function as,

localid="1650899720458" ψx=43x...2for localid="1650899725784" 0≤x≤0.75nmand,

localid="1650899733838" ψx=431nm-x...3for localid="1650899738891" 0.75nm≤x≤1nm

Now, equation 2 and 3 gives,

localid="1650898727768" ψx2=163x2and localid="1650899746880" ψx2=481-x2, where localid="1650899754028" ψx2has a unit of localid="1650899762684" nm-1.

Therefore, the graph of the probability density should be as follows:

04

Part c Step 1: Drawing the dot pictures

The particle is most likely to be found at the points where ψx2is a maximum. We can draw the dot picture according to the graph of probability density as shown earlier:

05

Part d Step 1: Determination of probability

The probability of the particle in the interval of 0≤≤x≤0.25nm, can be determined by taking the equation ψx2=163x2as,

P0≤x≤0.25=∫00.25ψx2dxP0≤x≤0.25=∫00.25163x2dxP0≤x≤0.25=163x3300.25P0≤x≤0.25=136P0≤x≤0.25=0.028

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