Another Quick Couple of Infinite Well Questions

In summary, the homework statement discusses two problems involving wavefunctions and the probability of obtaining certain energies. In problem 1, the wavefunction is given as \Psi(x,0) = A(\psi_1(x) + \psi_2(x)), and the question asks for the probability of getting E1 or E2 as the energy. The solution involves normalizing the wavefunction and finding the values of c_n^2, which is found to be 1/2 for each energy level. For problem 2, the wavefunction is \Psi(x,0) = Ax; 0<= x <= a/2 ; A(a-x); a/2<= x <= a, and the question asks for the probability of
  • #1
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Homework Statement


Problem 1. If I had a wavefunction: [tex] \Psi(x,0) = A(\psi_1(x) + \psi_2(x))[/tex]

What is the probability of getting E1 or E2 as your energy?

Problem 2 You have a wavefunction:

[tex] \Psi(x,0) = Ax; 0<= x <= a/2 ; A(a-x); a/2<= x <= a [/tex]
What is the probability that an energy measurement would yield E1.

Homework Equations


Given Up above

The Attempt at a Solution


For problem 1, i feel the probabilities should be 1/2 for each of them, but this seems too easy. I also normalized and found Psi(x,t), A = 1/sqrt(2)

For problem 2 I'm completely lost
There are an infinite amount of energy levels so shouldn't the probability be 0, but then this doesn't make any sense. I feel I'm missing something. Are the probabilities not that easy?
 
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  • #2
wait, just remembered...i got to find c_n^2...
 

1. What is an infinite well?

An infinite well is a theoretical model used in quantum mechanics to describe a particle confined to a certain space. The potential energy within the well is infinite, meaning the particle cannot escape, but the potential energy outside the well is zero, allowing the particle to move freely.

2. How does the width of the well affect the energy levels?

The width of the well directly affects the energy levels of a particle in an infinite well. A wider well will have more energy levels, while a narrower well will have fewer energy levels. This is because the width of the well determines the wavelength of the particle, which in turn affects its energy.

3. What happens to the energy levels as the particle's mass increases?

As the particle's mass increases, the energy levels of the infinite well increase as well. This is because the particle's momentum and wavelength are inversely proportional to its mass, so a heavier particle will have a smaller wavelength and therefore a higher energy level.

4. Can a particle in an infinite well have negative energy?

No, a particle in an infinite well cannot have negative energy. The potential energy of the well is always positive, so the total energy of the particle must also be positive. However, a particle can have a negative kinetic energy, meaning it is confined to the well and cannot escape.

5. How does the particle's position change as it moves from one energy level to another?

The particle's position does not change when it moves from one energy level to another in an infinite well. This is because the particle is confined to the well and cannot move beyond its boundaries. The only thing that changes is the particle's energy, which determines the wavelength and momentum of the particle.

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