AP Physics 2 Flashcards: Electromagnetic Waves

What this deck covers

This deck focuses on Electromagnetic Waves, 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: State the order of electromagnetic spectrum regions by increasing frequency.

Answer: Radio, Microwave, Infrared, Visible, UV, X-ray, Gamma. Listed from lowest to highest frequency across the spectrum.

Flashcard 2: In which region do electromagnetic waves have the greatest energy per photon?

Answer: Gamma rays. Highest frequency means highest energy per photon.

Flashcard 3: Identify the electromagnetic wave with wavelengths shorter than visible light.

Answer: Ultraviolet rays. UV wavelengths are shorter than violet light at 400 nm.

Flashcard 4: Which electromagnetic waves are used in sterilization of medical equipment?

Answer: Ultraviolet (UV) rays. UV radiation kills bacteria and viruses effectively.

Flashcard 5: State the relationship between frequency and wavelength of electromagnetic waves.

Answer: $c = f \times \text{wavelength}$, where $c$ is the speed of light. Shows how speed equals frequency times wavelength in electromagnetic waves.

Flashcard 6: What is the typical wavelength range for microwaves?

Answer: 1 mm to 1 m. Microwaves fall between radio waves and infrared radiation.

Flashcard 7: What is the range of wavelengths for visible light?

Answer: Approximately 400 nm to 700 nm. This range covers the spectrum from violet to red light wavelengths.

Flashcard 8: What is the range of wavelengths for visible light?

Answer: Approximately 400 nm to 700 nm. This range covers the spectrum from violet to red light wavelengths.

Flashcard 9: What is the frequency of a photon with an energy of $4 \times 10^{-19} \text{ J}$?

Answer: $6.05 \times 10^{14} \text{ Hz}$. Using $f = E/h$ with given energy and Planck's constant.

Flashcard 10: What is the typical frequency range for infrared waves?

Answer: $10^{11} \text{ Hz}$ to $10^{14} \text{ Hz}$. Infrared falls between microwaves and visible light frequencies.

Flashcard 11: Which electromagnetic waves have the longest wavelength?

Answer: Radio waves. Radio waves have the lowest frequencies and longest wavelengths.

Flashcard 12: State the order of electromagnetic spectrum regions by increasing frequency.

Answer: Radio, Microwave, Infrared, Visible, UV, X-ray, Gamma. Listed from lowest to highest frequency across the spectrum.

Flashcard 13: Identify the electromagnetic wave with the highest frequency.

Answer: Gamma rays. Gamma rays have the shortest wavelengths and highest frequencies.

Flashcard 14: Identify the electromagnetic spectrum region with the shortest wavelength.

Answer: Gamma rays. Shortest wavelength corresponds to highest frequency and energy.

Flashcard 15: Name the electromagnetic wave used in night vision technology.

Answer: Infrared. Detects heat radiation emitted by objects in darkness.

Flashcard 16: What is the primary application of microwaves in the kitchen?

Answer: Heating food. Microwaves excite water molecules causing food to heat up.

Flashcard 17: Identify the electromagnetic spectrum region used for thermal imaging.

Answer: Infrared. Infrared radiation is emitted by warm objects for heat detection.

Flashcard 18: State the formula for energy of a photon.

Answer: $E = h \times f$, where $h$ is Planck's constant. This shows photon energy is proportional to frequency.

Flashcard 19: What is the wavelength of a 100 MHz radio wave?

Answer: 3 m. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and $f = 100 \times 10^6$ Hz.

Flashcard 20: Identify the electromagnetic spectrum region with the shortest wavelength.

Answer: Gamma rays. Shortest wavelength corresponds to highest frequency and energy.

Flashcard 21: What is Planck's constant value?

Answer: $6.626 \times 10^{-34} \text{ J}\times\text{s}$. This fundamental constant relates photon energy to frequency.

Flashcard 22: Find the frequency of light with a wavelength of 600 nm in a vacuum.

Answer: $5 \times 10^{14} \text{ Hz}$. Using $f = c/\lambda$ with $c = 3 \times 10^8$ m/s and $\lambda = 600 \times 10^{-9}$ m.

Flashcard 23: Which electromagnetic wave is used in radar technology?

Answer: Microwaves. Microwaves reflect off objects for distance and speed detection.

Flashcard 24: What is the primary use of X-rays in the medical field?

Answer: Imaging internal body structures. X-rays penetrate soft tissue but are absorbed by bones.

Flashcard 25: What is the typical wavelength range for microwaves?

Answer: 1 mm to 1 m. Microwaves fall between radio waves and infrared radiation.

Flashcard 26: What is the wavelength of a 100 MHz radio wave?

Answer: 3 m. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and $f = 100 \times 10^6$ Hz.

Flashcard 27: Find the frequency of light with a wavelength of 600 nm in a vacuum.

Answer: $5 \times 10^{14} \text{ Hz}$. Using $f = c/\lambda$ with $c = 3 \times 10^8$ m/s and $\lambda = 600 \times 10^{-9}$ m.

Flashcard 28: Which electromagnetic wave is used in radar technology?

Answer: Microwaves. Microwaves reflect off objects for distance and speed detection.

Flashcard 29: What part of the electromagnetic spectrum is used in remote controls?

Answer: Infrared. Infrared LEDs transmit signals to electronic devices.

Flashcard 30: Find the wavelength of a gamma ray with frequency $3 \times 10^{19} \text{ Hz}$.

Answer: $1 \times 10^{-11} \text{ m}$. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and given frequency.

Flashcard 31: Identify the electromagnetic wave with the lowest energy.

Answer: Radio waves. Longest wavelength means lowest frequency and lowest energy.

Flashcard 32: What is the speed of electromagnetic waves in a vacuum?

Answer: $3 \times 10^8 \text{ m/s}$. This is the universal constant for all electromagnetic waves in vacuum.

Flashcard 33: Which region of the electromagnetic spectrum is used in cellular communication?

Answer: Microwaves. Microwaves penetrate atmosphere well for long-distance communication.

Flashcard 34: What is the wavelength of light with a frequency of $6 \times 10^{14} \text{ Hz}$?

Answer: 500 nm. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and given frequency.

Flashcard 35: Find the energy of a photon with frequency $5 \times 10^{14} \text{ Hz}$.

Answer: $3.313 \times 10^{-19} \text{ J}$. Using $E = hf$ with $h = 6.626 \times 10^{-34}$ J·s and given frequency.

Flashcard 36: In which region do electromagnetic waves have the greatest energy per photon?

Answer: Gamma rays. Highest frequency means highest energy per photon.

Flashcard 37: State the relationship between frequency and wavelength of electromagnetic waves.

Answer: $c = f \times \text{wavelength}$, where $c$ is the speed of light. Shows how speed equals frequency times wavelength in electromagnetic waves.

Flashcard 38: What region of the electromagnetic spectrum is visible to the human eye?

Answer: Visible light. Human eyes detect wavelengths roughly from 400-700 nanometers.

Flashcard 39: What is the frequency of a photon with an energy of $4 \times 10^{-19} \text{ J}$?

Answer: $6.05 \times 10^{14} \text{ Hz}$. Using $f = E/h$ with given energy and Planck's constant.

Flashcard 40: Which electromagnetic waves are commonly used in communication satellites?

Answer: Microwaves. Microwaves penetrate atmosphere for satellite-to-Earth communication.

Flashcard 41: What is the wavelength of light with a frequency of $6 \times 10^{14} \text{ Hz}$?

Answer: 500 nm. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and given frequency.

Flashcard 42: Find the wavelength of a gamma ray with frequency $3 \times 10^{19} \text{ Hz}$.

Answer: $1 \times 10^{-11} \text{ m}$. Using $\lambda = c/f$ with $c = 3 \times 10^8$ m/s and given frequency.

Flashcard 43: Identify the electromagnetic wave with the highest frequency.

Answer: Gamma rays. Gamma rays have the shortest wavelengths and highest frequencies.

Flashcard 44: Which electromagnetic wave is primarily responsible for sunburn?

Answer: Ultraviolet (UV) rays. UV radiation damages skin cells causing sunburn and cancer.

Flashcard 45: What is the frequency range for X-rays?

Answer: Approximately $10^{16} \text{ Hz}$ to $10^{19} \text{ Hz}$. X-rays fall between UV and gamma rays in frequency.

Flashcard 46: Find the frequency of ultraviolet light with wavelength 250 nm.

Answer: $1.2 \times 10^{15} \text{ Hz}$. Using $f = c/\lambda$ with $c = 3 \times 10^8$ m/s and $\lambda = 250 \times 10^{-9}$ m.

Flashcard 47: What region of the electromagnetic spectrum is visible to the human eye?

Answer: Visible light. Human eyes detect wavelengths roughly from 400-700 nanometers.

Flashcard 48: What is the speed of electromagnetic waves in a vacuum?

Answer: $3 \times 10^8 \text{ m/s}$. This is the universal constant for all electromagnetic waves in vacuum.

Flashcard 49: Find the frequency of ultraviolet light with wavelength 250 nm.

Answer: $1.2 \times 10^{15} \text{ Hz}$. Using $f = c/\lambda$ with $c = 3 \times 10^8$ m/s and $\lambda = 250 \times 10^{-9}$ m.

Flashcard 50: Which electromagnetic waves have the longest wavelength?

Answer: Radio waves. Radio waves have the lowest frequencies and longest wavelengths.

Flashcard 51: State the formula for energy of a photon.

Answer: $E = h \times f$, where $h$ is Planck's constant. This shows photon energy is proportional to frequency.

Flashcard 52: Which electromagnetic wave is primarily responsible for sunburn?

Answer: Ultraviolet (UV) rays. UV radiation damages skin cells causing sunburn and cancer.

Flashcard 53: What is the primary use of X-rays in the medical field?

Answer: Imaging internal body structures. X-rays penetrate soft tissue but are absorbed by bones.

Flashcard 54: Which electromagnetic waves are commonly used in communication satellites?

Answer: Microwaves. Microwaves penetrate atmosphere for satellite-to-Earth communication.

Flashcard 55: Identify the electromagnetic spectrum region used for thermal imaging.

Answer: Infrared. Infrared radiation is emitted by warm objects for heat detection.

Flashcard 56: Which electromagnetic wave is used in MRI technology?

Answer: Radio waves. MRI uses radiofrequency waves to excite hydrogen nuclei.

Flashcard 57: What part of the electromagnetic spectrum is used in remote controls?

Answer: Infrared. Infrared LEDs transmit signals to electronic devices.

Flashcard 58: What is the unit of frequency for electromagnetic waves?

Answer: Hertz (Hz). Hertz measures cycles per second for wave frequency.

Flashcard 59: State the relationship between energy and frequency of electromagnetic waves.

Answer: Energy is directly proportional to frequency. Higher frequency photons carry more energy per quantum.

Flashcard 60: Find the energy of a photon with frequency $5 \times 10^{14} \text{ Hz}$.

Answer: $3.313 \times 10^{-19} \text{ J}$. Using $E = hf$ with $h = 6.626 \times 10^{-34}$ J·s and given frequency.

Flashcard 61: Identify the electromagnetic wave with the lowest energy.

Answer: Radio waves. Longest wavelength means lowest frequency and lowest energy.

Flashcard 62: Which electromagnetic wave is used in MRI technology?

Answer: Radio waves. MRI uses radiofrequency waves to excite hydrogen nuclei.

Flashcard 63: Name the electromagnetic wave primarily used for broadcasting.

Answer: Radio waves. Radio waves carry audio and video signals over long distances.

Flashcard 64: Which electromagnetic waves are absorbed by ozone in the atmosphere?

Answer: Ultraviolet (UV) rays. Ozone layer absorbs harmful UV radiation protecting Earth's surface.

Flashcard 65: Name the electromagnetic wave used in night vision technology.

Answer: Infrared. Detects heat radiation emitted by objects in darkness.

Flashcard 66: Which electromagnetic waves are used in television broadcasting?

Answer: Radio waves. Radio waves carry television signals through the atmosphere.

Flashcard 67: Identify the electromagnetic wave with wavelengths shorter than visible light.

Answer: Ultraviolet rays. UV wavelengths are shorter than violet light at 400 nm.

Flashcard 68: What is the unit of frequency for electromagnetic waves?

Answer: Hertz (Hz). Hertz measures cycles per second for wave frequency.

Flashcard 69: Which region of the electromagnetic spectrum is used in cellular communication?

Answer: Microwaves. Microwaves penetrate atmosphere well for long-distance communication.

Flashcard 70: Which electromagnetic waves are absorbed by ozone in the atmosphere?

Answer: Ultraviolet (UV) rays. Ozone layer absorbs harmful UV radiation protecting Earth's surface.

Flashcard 71: Which electromagnetic waves are used in sterilization of medical equipment?

Answer: Ultraviolet (UV) rays. UV radiation kills bacteria and viruses effectively.

Flashcard 72: What is the primary application of microwaves in the kitchen?

Answer: Heating food. Microwaves excite water molecules causing food to heat up.

Flashcard 73: What is the frequency range for X-rays?

Answer: Approximately $10^{16} \text{ Hz}$ to $10^{19} \text{ Hz}$. X-rays fall between UV and gamma rays in frequency.

Flashcard 74: State the relationship between energy and frequency of electromagnetic waves.

Answer: Energy is directly proportional to frequency. Higher frequency photons carry more energy per quantum.

Flashcard 75: What is the typical frequency range for infrared waves?

Answer: $10^{11} \text{ Hz}$ to $10^{14} \text{ Hz}$. Infrared falls between microwaves and visible light frequencies.

Flashcard 76: Which electromagnetic waves are used in television broadcasting?

Answer: Radio waves. Radio waves carry television signals through the atmosphere.

Flashcard 77: What is Planck's constant value?

Answer: $6.626 \times 10^{-34} \text{ J}\times\text{s}$. This fundamental constant relates photon energy to frequency.

Flashcard 78: Name the electromagnetic wave primarily used for broadcasting.

Answer: Radio waves. Radio waves carry audio and video signals over long distances.