Question 1

In the double-slit experiment with monochromatic light, what does the intensity pattern observed on the screen primarily represent?

Accepted Answer

The probability distribution for where individual photons will strike the screen.

Question 2

Which of the following best explains why a single photon can produce an interference pattern over time in a double-slit experiment?

Accepted Answer

The photon behaves as a wave, and its probability amplitude interferes with itself.

Question 3

In a single-slit diffraction experiment, the position of the first dark fringe is given by which equation?

Accepted Answer

$$a \sin \$$theta_1$$ = \lambda$$

Question 4

If the slit width $$a is $$decreased in a single-slit diffraction experiment, what happens to the uncertainty in the photon's momentum component $$p_y$$?

Accepted Answer

The uncertainty in $$p_y$$ increases.

Question 5

Which equation expresses the Heisenberg uncertainty principle for position and momentum?

Accepted Answer

$$\Delta x \Delta p_x \geq \frac{\hbar}{2}$$

Question 6

A photon described by a single sinusoidal wave has a perfectly defined momentum. What does this imply about its position uncertainty?

Accepted Answer

Its position uncertainty is infinite.

Question 7

What is the physical significance of the equation $$\Delta t \Delta E \geq \frac{\hbar}{2}$$?

Accepted Answer

It expresses the uncertainty principle for energy and time.

Question 8

In the context of the single-slit experiment, if the wavelength $$\lambda is $$much smaller than the slit width $$a$$, what can be said about the angle $$\$$theta_1$$ for the first minimum?

Accepted Answer

$$\sin \$$theta_1$$ \approx \$$theta_1$$ \approx \frac{\lambda}{a}$$

Question 9

Why does superimposing two sinusoidal waves of different wavelengths localize a photon more in space?

Accepted Answer

The resulting wave packet is more confined, reducing position uncertainty.

Question 10

A photomultiplier detector is used to count photons at different positions on a screen in a double-slit experiment. What does the resulting count distribution reveal?

Accepted Answer

The probability distribution for photon arrival positions.

Question 11

If you attempt to measure both the position and momentum of a photon with high precision, what fundamental principle limits your accuracy?

Accepted Answer

Heisenberg uncertainty principle

Question 12

In a single-slit diffraction experiment, what is the relationship between the slit width $$a$$ and the spread of the diffraction pattern?

Accepted Answer

A narrower slit produces a broader diffraction pattern.

Question 13

Which of the following is a direct consequence of the wave-particle duality of light?

Accepted Answer

Light can produce both interference patterns and discrete detection events.

Question 14

Given $$p_x = h/\lambda$$ for a photon, what is the minimum uncertainty in $$p_y$$ for a photon passing through a slit of width $$a$$?

Accepted Answer

$$\Delta p_y \geq \frac{h}{a}$$

Question 15

If a photon is described by a wave packet (a superposition of many waves), what can be said about its momentum and position uncertainties?

Accepted Answer

Both uncertainties are finite and related by the uncertainty principle.

Question 16

Which of the following best describes the effect of measuring the energy of a photon very precisely over a short time interval?

Accepted Answer

The uncertainty in the time interval increases.

Light: Wave-Particle Duality, Probability, and Uncertainty

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