AP Physics 2 Flashcards: Quantum Theory And Wave Particle Duality

What this deck covers

This deck focuses on Quantum Theory And Wave Particle Duality, giving you a quick way to review the definitions, rules, and examples that matter most for AP Physics 2.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: Which experiment demonstrated the wave nature of electrons?

Answer: Davisson-Germer experiment. Electron diffraction confirmed de Broglie's matter wave hypothesis.

Flashcard 2: Which constant appears in both $E = hf$ and $\lambda = \frac{h}{p}$?

Answer: Planck's constant, $h$. Universal quantum constant in energy and wave relations.

Flashcard 3: Convert $\lambda = 450 \text{ nm}$ to energy of a photon.

Answer: $E = \frac{hc}{\lambda}$. Apply energy-wavelength formula with given wavelength value.

Flashcard 4: State the formula for calculating momentum $p$ of a photon.

Answer: $p = \frac{h}{\lambda}$. Photon momentum derived from de Broglie wavelength relation.

Flashcard 5: Calculate de Broglie wavelength for $p = 2 \times 10^{-27} \text{ kg m/s}$.

Answer: $\lambda = \frac{h}{p}$. Apply de Broglie formula with given momentum value.

Flashcard 6: What phenomenon does the photoelectric effect explain?

Answer: Ejection of electrons by light. Light removes electrons from material surfaces.

Flashcard 7: What does the Heisenberg uncertainty principle state?

Answer: $\Delta x \Delta p \geq \frac{\hbar}{2}$. Position and momentum cannot both be precisely known simultaneously.

Flashcard 8: Find the energy of a photon with wavelength $\lambda = 500 \text{ nm}$.

Answer: Use $E = \frac{hc}{\lambda}$. Substitute wavelength into energy-wavelength relationship.

Flashcard 9: What is the wave-particle duality concept?

Answer: Particles exhibit both wave-like and particle-like properties. Fundamental quantum principle describing matter and energy behavior.

Flashcard 10: What is the relationship between wavelength and frequency?

Answer: Inversely proportional, $c = f\lambda$. Higher frequency means shorter wavelength for constant speed.

Flashcard 11: What is the work function $\phi$?

Answer: Minimum energy needed to remove an electron from a material. Energy threshold for electron emission from surface.

Flashcard 12: What is the photoelectric effect?

Answer: Emission of electrons when light hits a material. Light-induced electron emission from metal surfaces.

Flashcard 13: State Planck's constant value.

Answer: 6.62607015 × 10^{-34} Js. Fundamental constant relating energy to frequency in quantum mechanics.

Flashcard 14: What phenomenon does the photoelectric effect explain?

Answer: Ejection of electrons by light. Light removes electrons from material surfaces.

Flashcard 15: Determine the frequency of a photon with energy $E$.

Answer: $f = \frac{E}{h}$. Rearranged form of $E = hf$ to solve for frequency.

Flashcard 16: What does $\lambda$ represent in de Broglie wavelength?

Answer: Wavelength of a particle. Matter wavelength in de Broglie's wave hypothesis.

Flashcard 17: Convert $\lambda = 450 \text{ nm}$ to energy of a photon.

Answer: $E = \frac{hc}{\lambda}$. Apply energy-wavelength formula with given wavelength value.

Flashcard 18: How are wavelength and momentum related in de Broglie's hypothesis?

Answer: Inversely proportional, $\lambda = \frac{h}{p}$. Higher momentum gives shorter wavelength.

Flashcard 19: What does $\lambda$ represent in de Broglie wavelength?

Answer: Wavelength of a particle. Matter wavelength in de Broglie's wave hypothesis.

Flashcard 20: What is the work function $\phi$?

Answer: Minimum energy needed to remove an electron from a material. Energy threshold for electron emission from surface.

Flashcard 21: What is the wave-particle duality concept?

Answer: Particles exhibit both wave-like and particle-like properties. Fundamental quantum principle describing matter and energy behavior.

Flashcard 22: How are wavelength and momentum related in de Broglie's hypothesis?

Answer: Inversely proportional, $\lambda = \frac{h}{p}$. Higher momentum gives shorter wavelength.

Flashcard 23: Identify the relationship for kinetic energy of ejected electrons.

Answer: $KE = hf - \phi$. Einstein's photoelectric equation for electron kinetic energy.

Flashcard 24: What is the significance of Planck's constant?

Answer: Relates energy and frequency. Quantum of action linking energy and frequency.

Flashcard 25: What is Heisenberg's uncertainty relation in terms of position and momentum?

Answer: $\Delta x \Delta p \geq \frac{\hbar}{2}$. Fundamental quantum limit on simultaneous measurements.

Flashcard 26: What is the symbol $\hbar$?

Answer: Reduced Planck's constant, $\hbar = \frac{h}{2\pi}$. Appears in angular momentum and uncertainty relations.

Flashcard 27: What is the relation between frequency $f$ and wavelength $\lambda$?

Answer: $c = f\lambda$. Speed of light equals frequency times wavelength.

Flashcard 28: What is the dual nature of light?

Answer: Wave and particle. Light exhibits both wave and particle characteristics.

Flashcard 29: How does increasing frequency affect photon energy?

Answer: Photon energy increases with frequency. Direct proportionality from $E = hf$ relationship.

Flashcard 30: What effect does increasing photon frequency have on its wavelength?

Answer: Wavelength decreases. Inverse relationship from $c = f\lambda$ at constant speed.

Flashcard 31: State the formula for calculating momentum $p$ of a photon.

Answer: $p = \frac{h}{\lambda}$. Photon momentum derived from de Broglie wavelength relation.

Flashcard 32: Determine the frequency of a photon with energy $E$.

Answer: $f = \frac{E}{h}$. Rearranged form of $E = hf$ to solve for frequency.

Flashcard 33: What is the relationship between wavelength and frequency?

Answer: Inversely proportional, $c = f\lambda$. Higher frequency means shorter wavelength for constant speed.

Flashcard 34: Find the de Broglie wavelength of an electron with momentum $p$.

Answer: $\lambda = \frac{h}{p}$. Matter wavelength formula using momentum.

Flashcard 35: What is the relationship between energy and frequency of a photon?

Answer: $E = hf$. Planck's quantum energy formula for photons.

Flashcard 36: What effect does increasing photon frequency have on its wavelength?

Answer: Wavelength decreases. Inverse relationship from $c = f\lambda$ at constant speed.

Flashcard 37: What does the Heisenberg uncertainty principle state?

Answer: $\Delta x \Delta p \geq \frac{\hbar}{2}$. Position and momentum cannot both be precisely known simultaneously.

Flashcard 38: What is the de Broglie wavelength formula?

Answer: $\lambda = \frac{h}{p}$. Relates particle wavelength to momentum through Planck's constant.

Flashcard 39: What did de Broglie propose about matter?

Answer: Matter has wave properties. All matter exhibits wavelike behavior.

Flashcard 40: What does a higher frequency imply for a photon's energy?

Answer: Higher energy. Energy directly proportional to frequency via $E = hf$.

Flashcard 41: Identify the formula for energy of a photon.

Answer: $E = hf$. Directly proportional relationship between photon energy and frequency.

Flashcard 42: Find the momentum of a photon with wavelength $\lambda = 700 \text{ nm}$.

Answer: $p = \frac{h}{\lambda}$. Use momentum formula with given wavelength value.

Flashcard 43: What is the significance of the double-slit experiment?

Answer: Demonstrates wave-particle duality. Shows particles behave as both waves and particles.

Flashcard 44: Which constant is used to describe quantization of energy?

Answer: Planck's constant, $h$. Fundamental constant in energy quantization formulas.

Flashcard 45: Which experiment demonstrated the wave nature of electrons?

Answer: Davisson-Germer experiment. Electron diffraction confirmed de Broglie's matter wave hypothesis.

Flashcard 46: How do you calculate the energy of a photon given its frequency?

Answer: $E = hf$. Direct application of Planck's energy-frequency relation.

Flashcard 47: What is the de Broglie wavelength formula?

Answer: $\lambda = \frac{h}{p}$. Relates particle wavelength to momentum through Planck's constant.

Flashcard 48: What principle limits simultaneous knowledge of position and momentum?

Answer: Heisenberg uncertainty principle. Fundamental limit on measurement precision in quantum mechanics.

Flashcard 49: What is the photoelectric effect?

Answer: Emission of electrons when light hits a material. Light-induced electron emission from metal surfaces.

Flashcard 50: Find the energy of a photon with wavelength $\lambda = 500 \text{ nm}$.

Answer: Use $E = \frac{hc}{\lambda}$. Substitute wavelength into energy-wavelength relationship.

Flashcard 51: What is the relation between frequency $f$ and wavelength $\lambda$?

Answer: $c = f\lambda$. Speed of light equals frequency times wavelength.

Flashcard 52: What is the dual nature of light?

Answer: Wave and particle. Light exhibits both wave and particle characteristics.

Flashcard 53: Find the de Broglie wavelength of an electron with momentum $p$.

Answer: $\lambda = \frac{h}{p}$. Matter wavelength formula using momentum.

Flashcard 54: What principle limits simultaneous knowledge of position and momentum?

Answer: Heisenberg uncertainty principle. Fundamental limit on measurement precision in quantum mechanics.

Flashcard 55: What is the equation for the energy of a photon in terms of wavelength?

Answer: $E = \frac{hc}{\lambda}$. Combines speed of light with Planck's constant and wavelength.

Flashcard 56: What is the symbol $\hbar$?

Answer: Reduced Planck's constant, $\hbar = \frac{h}{2\pi}$. Appears in angular momentum and uncertainty relations.

Flashcard 57: Calculate de Broglie wavelength for $p = 2 \times 10^{-27} \text{ kg m/s}$.

Answer: $\lambda = \frac{h}{p}$. Apply de Broglie formula with given momentum value.

Flashcard 58: What is the significance of Planck's constant?

Answer: Relates energy and frequency. Quantum of action linking energy and frequency.

Flashcard 59: Which constant appears in both $E = hf$ and $\lambda = \frac{h}{p}$?

Answer: Planck's constant, $h$. Universal quantum constant in energy and wave relations.

Flashcard 60: What is the relationship between energy and frequency of a photon?

Answer: $E = hf$. Planck's quantum energy formula for photons.

Flashcard 61: What is the significance of the double-slit experiment?

Answer: Demonstrates wave-particle duality. Shows particles behave as both waves and particles.

Flashcard 62: What does a higher frequency imply for a photon's energy?

Answer: Higher energy. Energy directly proportional to frequency via $E = hf$.

Flashcard 63: How do you calculate the energy of a photon given its frequency?

Answer: $E = hf$. Direct application of Planck's energy-frequency relation.

Flashcard 64: Which equation represents the photoelectric effect?

Answer: $KE = hf - \phi$. Kinetic energy equals incident photon energy minus work function.

Flashcard 65: Identify the relationship for kinetic energy of ejected electrons.

Answer: $KE = hf - \phi$. Einstein's photoelectric equation for electron kinetic energy.

Flashcard 66: Which constant is used to describe quantization of energy?

Answer: Planck's constant, $h$. Fundamental constant in energy quantization formulas.

Flashcard 67: What did de Broglie propose about matter?

Answer: Matter has wave properties. All matter exhibits wavelike behavior.

Flashcard 68: What is Heisenberg's uncertainty relation in terms of position and momentum?

Answer: $\Delta x \Delta p \geq \frac{\hbar}{2}$. Fundamental quantum limit on simultaneous measurements.

Flashcard 69: Identify the formula for energy of a photon.

Answer: $E = hf$. Directly proportional relationship between photon energy and frequency.

Flashcard 70: What is the principle behind quantum mechanics?

Answer: Wave-particle duality. Core concept underlying all quantum mechanical phenomena.

Flashcard 71: What is the equation for the energy of a photon in terms of wavelength?

Answer: $E = \frac{hc}{\lambda}$. Combines speed of light with Planck's constant and wavelength.

Flashcard 72: Which equation represents the photoelectric effect?

Answer: $KE = hf - \phi$. Kinetic energy equals incident photon energy minus work function.

Flashcard 73: What is the principle behind quantum mechanics?

Answer: Wave-particle duality. Core concept underlying all quantum mechanical phenomena.

Flashcard 74: State Planck's constant value.

Answer: 6.62607015 × 10^{-34} Js. Fundamental constant relating energy to frequency in quantum mechanics.

Flashcard 75: How does increasing frequency affect photon energy?

Answer: Photon energy increases with frequency. Direct proportionality from $E = hf$ relationship.