Science Test 4 - Physics Flashcards
What are the two types of waves?
Mechanical waves and electromagnetic waves.
What are mechanical waves + example?
Require a medium, e.g. waterwaves, soundwaves.
What is the wavelength?
The distance between any two identical points on a wave?
What is the acronym for the electromagnetic spectrum?
Red monkeys in vans use x-ray glasses.
What are transverse waves?
The particles vibrate perpendicular to the direction of energy (Up and down).
What are longitudinal waves?
The particles vibrate in the same direction as enery movement (side to side).
What is the amplitude?
The maximum distance from the midpoint of the wave.
What are all the types of waves in the electromagnetic spectrum?
Radio waves, microwaves, infrared, visible, ultra violet, x-ray, gamma waves.
What is a vaccuum?
An area with no particles.
What is a medium?
A medium is the thing that a wave travels through.
If the particles aren’t moving in the wave, then what are they doing?
The particles move up or down or side to side.
What are electromagnetic waves+example/?
Do not require a medium, e.g. lightwaves.
Do shorter wavelengths have lower or higher frequencies?
HIgher frequencies.
What happens if an object is translucent?
Only some of the light will be transmitted
What happens if an object is transparent?
The light will mostly be transmitted through the object.
What do waves transport and not transport?
Waves transport energy, but they do not transfer the matter/particles.
Where do waves come from?
All waves come from vibrations.
Increased amplitude = …
Decreased amplitude = … (in light waves)
Brighter
Darker/Dimmer
What are electromagnetic waves and do they require a medium?
Electromagnetic waves are transverse waves that carry radiation energy, do not require a medium.
What is the frequency?
How many waves per second
Luminous
Makes their own light
What happens if an object is opaque?
No light can be transmitted.
Diverge + example
Light rays can diverge, meaning spread out e.g. flashlight
Non-luminous
Objects are only seen by the lights they reflect
When does reflection occur?
When light hits a smooth surface
What happens when an object absorbs light energy?
It is transformed into heat energy. Therefore, the more light energy absorbed the hotter an object gets.
What is the slowest thing light travels in?
Diamond (Most dense)
When does diffuse reflection occur?
When light rays hits a rough surface
Does light travel faster in a more or less dense medium?
Less dense
What are waves?
Waves are the movement of energy which is caused by vibration.
What is the law of reflection?
A light ray coming in will always be reflected at the same angle on the other side.
Converge
Light rays can converge, meaning come together e.g. human eye
What is the angle of incidence?
The angle of which light enters.
What do frequency and wavelength effect for light?
Colour
What is frequency related to in sound waves?
Pitch - Higher frequency, higher pitch of the sound
What is the measure for amplitude?
Decibels (dB)
What does amplitude for light effect?
Brightness
Any sound waves below human hearing are called …
Infrasound
What are factors effecting the speed of sound?
Quality of material and the temperature of the material
When light strikes a boundary the light can be….
Reflected, transmitted, absorbed, scattered
What is refraction?
When a wave travels into a new medium and the speed changes, the wave changes direction which is refraction.
Is the refraction towards the normal in a slower or faster medium?
Slower
Is the refraction away from the normal in a slower or faster medium?
Faster
What is the fastest thing light travels in?
Air/vacuum (Least dense)
Are sound wave longtudinal or transverse?
Longtudinal
What is the amplitude related to in sound waves?
Loudness - Greater amplitude, louder sound
Any sound waves above human hearing are called …
Ultrasound
How do you work out the speed of something?
Speed = Distance/Time
Sound can be like light waves in the sense that…
Sound can be transmitted through materials, sound can be absorbed by materials and converted to heat, sound can be reflected and change direction when moving.
What are echoes?
When hard surfaces reflect sound waves.
What is the use of sonar?
The time difference between sending and receiving sound.
What is the speed of sound in air?
340m/s
