Modern Physics
A photon has a frequency of 5 \times 10^{14}
Hz. What is its energy? (Planck's constant Js)
3.313 \times 10^{-48}
J
1.325 \times 10^{-19}
J
3.313 \times 10^{48}
J
3.00 \times 10^{8}
J
A photon has an energy of 3.9756 \times 10^{-19}
J. What is its wavelength? (Planck's constant Js, speed of light m/s)
300 nm
400 nm
500 nm
600 nm
A photon with a wavelength of 600 nm travels from air (index of refraction ≈ 1) into glass (index of refraction = 1.5). What is the photon's new speed and wavelength in the glass?
Speed: 3.0 \times 10^8
m/s, Wavelength: 600 nm
Speed: 2.0 \times 10^8
m/s, Wavelength: 400 nm
Speed: 3.0 \times 10^8
m/s, Wavelength: 900 nm
Speed: 4.5 \times 10^8
m/s, Wavelength: 600 nm
An electron has a momentum of 6.626 \times 10^{-24}
kg m/s. What is its de Broglie wavelength? (Planck's constant Js)
0.01 nm
0.1 nm
1 nm
10 nm
Particle A has a mass of and a velocity of . Particle B has a mass of 2m
and a velocity of . How do their de Broglie wavelengths compare?
Particle A has twice the de Broglie wavelength of Particle B.
Particle A has half the de Broglie wavelength of Particle B.
Particle A has the same de Broglie wavelength as Particle B.
Particle A has four times the de Broglie wavelength of Particle B.
An electron has a kinetic energy of 2.41 J. Calculate its de Broglie wavelength, given its mass is 9.11 kg and Planck's constant is 6.626 Js.
0.5 nm
0.75 nm
1.0 nm
1.25 nm
Why is wave-particle duality not readily observed in macroscopic objects like baseballs?
Macroscopic objects do not have a wavelength.
The de Broglie wavelength of macroscopic objects is extremely small.
Macroscopic objects only exhibit particle-like behavior.
Wave-particle duality only applies to massless particles.

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How does decreasing the size of the box affect the energy levels of a particle in a one-dimensional box?
The energy levels become closer together.
The energy levels become further apart.
The energy levels remain the same.
The energy levels disappear.
In a hydrogen atom, are the energy levels for the electron continuous or discrete?
Continuous
Discrete
Both continuous and discrete depending on the electron's speed
Neither continuous nor discrete
What fundamental concept does quantum theory introduce that is not present in classical mechanics?
The continuous flow of energy.
The predictability of particle trajectories.
The quantization of energy levels.
The absolute certainty of measurements.