P6 - Waves and Optics Flashcards
What is a wave?
A wave is a disturbance that transfers energy from one place to another without transferring matter.
What are the two types of waves?
Transverse waves and longitudinal waves.
What are transverse waves?
Waves where the oscillations are perpendicular to the direction of wave travel. Example: Light waves.
What are longitudinal waves?
Waves where the oscillations are parallel to the direction of wave travel. Example: Sound waves.
What is amplitude?
The maximum displacement of a point on the wave from its rest position.
What is wavelength?
The distance between two consecutive crests or troughs in a wave.
What is frequency?
The number of complete waves passing a point per second. Measured in Hertz (Hz).
What is the formula for wave speed?
Wave speed (v) = Frequency (f) × Wavelength (λ)
How do you calculate frequency from wave speed and wavelength?
Frequency (f) = Wave speed (v) / Wavelength (λ)
How do you calculate wavelength from wave speed and frequency?
Wavelength (λ) = Wave speed (v) / Frequency (f)
What happens when waves are reflected?
When waves bounce off a surface, the angle of incidence equals the angle of reflection.
What happens when waves are refracted?
Waves change speed and direction as they pass from one medium to another.
What is diffraction?
The bending of waves around obstacles or through openings.
How do sound waves travel?
Sound waves are longitudinal waves that need a medium (solid, liquid, or gas) to travel through.
What is the speed of light?
The speed of light in a vacuum is approximately 3 × 10^8 m/s.
What is the electromagnetic spectrum?
A range of all the different frequencies of electromagnetic radiation, from radio waves to gamma rays.
How does the speed of a wave change in different media?
Waves travel faster in denser media like water, and slower in less dense media like air.
What are some uses of infrared radiation?
Used in remote controls, night-vision cameras, and thermal imaging.
What are some uses of microwaves?
Used in cooking, satellite communications, and radar.
What are some uses of ultraviolet radiation?
Used in sterilization, black lights, and tanning beds.
What are some uses of X-rays?
Used in medical imaging to view bones and internal structures.
What are some uses of gamma rays?
Used in cancer treatment, sterilizing medical equipment.
What are the dangers of ultraviolet radiation?
Can cause skin damage, eye damage, and increase the risk of cancer.
What are the dangers of X-rays and gamma rays?
Both can cause cell damage, increase cancer risk, and damage tissues.
What is constructive interference?
When two waves meet in phase, their amplitudes add together to make a larger wave.
What is destructive interference?
When two waves meet out of phase, their amplitudes cancel out to form a smaller wave.
What is the Doppler effect?
The change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source.
What is an echo?
A reflection of sound that can be heard after a delay.
How does the speed of sound change in different mediums?
Sound travels fastest in solids, slower in liquids, and slowest in gases.
What is total internal reflection?
The complete reflection of light inside a medium when the angle of incidence is greater than the critical angle.
What is the critical angle?
The angle of incidence above which total internal reflection occurs.
What part of the electromagnetic spectrum is visible to humans?
The visible light spectrum, which ranges from about 400 nm to 700 nm.
What are seismic waves?
Waves of energy that travel through the Earth, used to study earthquakes.
What are P-waves?
Primary waves, which are longitudinal and the fastest seismic waves. They can travel through solids, liquids, and gases.
What are S-waves?
Secondary waves, which are transverse and slower than P-waves. They can only travel through solids.
How do waves transfer energy?
Waves transfer energy through the oscillations of particles in a medium, without transferring matter.
How does light refract in water?
Light slows down and bends towards the normal when entering a denser medium like water.
What are wavefronts?
Imaginary lines or surfaces representing points of equal phase in a wave.
What is wave interference?
The interaction of two or more waves that results in either constructive or destructive interference.
What happens when light is reflected?
Light bounces off a surface, with the angle of incidence equal to the angle of reflection.
Can you give an example of diffraction?
Diffraction occurs when light passes through a narrow gap and spreads out, creating a pattern.
What are the main properties of waves?
Amplitude, frequency, wavelength, and speed.
What type of waves are electromagnetic waves?
Transverse waves.
What is the speed of sound in air?
Approximately 343 m/s at room temperature (20°C).
How does amplitude affect the loudness of sound?
Higher amplitude results in louder sound, while lower amplitude results in quieter sound.
