Download Klicker-questions, chapter 1 1. The figure shows the probability

Klicker-questions, chapter 1
1.
The figure shows the probability distribution for a particle in a given quantum state Ψ.
If we measure the position of the particle what value will we obtain?
5. The deBroglie wavelength is given by λ=h/p, where p is the momentum of the particle.Which of
these statements is correct?
a) The deBroglie wavelength of a particle is increasing when the energy of the particle is increasing
from 1 eV to 10 eV.
b) An electron and a proton is moving with the same velocity. The electron will then have a longer
deBroglie wavelength than the proton.
c) An electron and a proton have equal energies. The will then have equal deBroglie wavelengths.
6. What does Heisenberg's uncertainty relation
a)
b)
c)
∞
x =
∫ x Ψ ( x, t )
2
dx = 5
What does it mean?
−∞
a)
b)
If you measure the position of a particle over and over again, the average of these
measurements will give the value 5.
If you measure the position on a number of particles all in the same quantum state Ψ(x,t),
then the average of all measurements will be 5.
3. Assume the wave function of a particle is given by Ψ ( x, t ) = ei (kx −ωt )
If you measure the position of the particle where is the largest probability to find it?
a)
Around x=0.
b)
Depends of the time t.
c)
The probability to find the particle is the same everywhere.
4. The probability distribution for the position of a particle at time t is shown in the figure. At this
time the position is measured and the value 0.73 is obtained. What is the most probable value
to obtain the me position is measured again just a moment later?
a)
b)
c)
0.58
0.74
I don’t know.
h
2
say about the position and momentum of a particle?
a) We can never know the position of a particle exact.
b) We can know the position and momentum of a particle exact, but never at the same time.
c) We can know the position of the particle exact, but not the momentum.
I don’t know.
Around x=-1.
The probability distribution |Ψ(x,t)|2.
2. Assume that
σ xσ p ≥
Answers
1. a), 2 b), 3 c), 4 b), 5 b), 6 b),