Chapter 4 (Electromagnetic Energy) Flashcards
What is the velocity of all electromagnetic radiation?
The speed of light (3.00 × 10⁸ m/s)
This is a fundamental constant in physics.
What is the smallest quantity of electromagnetic energy?
Photon (or quantum)
Photons are massless particles that carry electromagnetic energy.
What is the relationship between frequency and wavelength?
Inverse (higher frequency = shorter wavelength)
This relationship is described by the equation c = λν.
What type of radiation is used in x-ray imaging?
Ionizing radiation (x-rays and gamma rays)
Ionizing radiation has enough energy to remove tightly bound electrons from atoms.
What does the wave-particle duality of electromagnetic energy describe?
Light acts as both a wave and a particle
This duality is a fundamental concept in quantum mechanics.
How does attenuation affect x-ray imaging?
It reduces beam intensity due to absorption and scattering
Attenuation is critical for producing contrast in x-ray images.
What are radiopaque materials?
Materials that absorb x-rays and appear bright on an image (e.g., bone)
These materials are useful in medical imaging to highlight certain areas.
What are radiolucent materials?
Materials that transmit x-rays and appear dark (e.g., lungs)
These materials allow x-rays to pass through, making them appear darker on images.
What does the Inverse Square Law state?
Intensity decreases with the square of the distance from the source
This law is important in understanding radiation exposure.
What is the relationship between photon energy and wavelength?
Inversely proportional (higher energy = shorter wavelength)
This relationship helps in understanding the electromagnetic spectrum.
What is the formula for photon energy?
E = hf (where h = Planck’s constant)
This formula is fundamental in quantum mechanics.
What does relativity state about matter and energy?
Matter and energy can be converted (E = mc²)
This equation shows the equivalence of mass and energy.
What is the difference between x-rays and gamma rays?
X-rays are produced by electrons, gamma rays by the nucleus
This distinction is important in understanding their origins and properties.
What happens to energy as frequency increases?
Energy increases
This is directly related to the photon energy formula.
What is a sine wave?
A graphical representation of electromagnetic radiation
It illustrates the oscillating electric and magnetic fields of electromagnetic waves.
What determines an x-ray’s penetration ability?
Wavelength and energy
Higher energy x-rays penetrate materials more effectively.
What does attenuation depend on?
Tissue type, density, and thickness
These factors influence how much x-ray energy is absorbed or scattered.
What is the primary difference between visible light and x-rays?
X-rays have higher energy and can ionize matter
This property makes x-rays useful in medical imaging but also potentially harmful.
What is ionization?
The removal of an electron from an atom
This process can lead to chemical changes in materials and is significant in radiation biology.
What is the electromagnetic spectrum?
The range of all electromagnetic waves from radio to gamma rays
It encompasses all types of electromagnetic radiation, each with different properties and uses.
