EOY YR 7 FLASHCARDS
what way do the particles in a transverse wave move?
in a TRANSVERSE WAVE, the particles go up and down as the energy moves forward. (Perpendicular
Eg. A water water wave
what way do the particles in longitudinal wave move?
In a LONGITUDINAL WAVE, the particles go back and forth as the energy moves forward.
Eg. A sound wave.
How is sound produced?
Sound is produced when particles in an object vibrate and the energy transfer to nearby particles coursing a longitudinal wave.
what does sound ussually travel through?
Normally these vibrations move subsequent particles in the air, but sound waves can also travel through a solid or liquid.
what is the medium?
The substance carrying the wave is known as the MEDIUM.
what can sound not travel through?
a vacuum where there are there are no particles, sound cannot travel at all.
speed of sound in air
300 m/s (metres per second).
speed of sound in water
The speed of sound in water is much faster at about 1470 m/s
why is the speed of sound in water quicker to in air
because there are more particles
light is what kind of wave
transverse
why is light special
it is special as it does not need a medium to travel through.
what is a vacuum
something with no particles
what is the speed of light in a vacuum
The speed of light in a vacuum is about 300milllion metres per second!
How does light travel?
IN a straight line
What does the light do
The light from the source hits the object, bounces off it (REFLECTS) and goes into your eye:
Law of reflection
The law of reflection states that “the angle of incidence equals the angle of reflection”
SOLIDS
Particles are close together and regularly arranged
They are held together with STRONG forces of attraction, and vibrate around fixed points.
LIQUIDS
Particles are close together, and arranged randomly
They are held together, but with much weaker forces, meaning they flow past each other through the container.
GASES
Particles are far apart, and arranged randomly
The attractive forces between them are VERY weak. The particles move quickly throughout the container.
ELEMENTS
are the different types of atoms that exist.
COMPOUND:
two or more different types of atom joined by chemical bonds. They are almost impossible to separate.
MIXTURE:
two or more different types of atoms or compounds that are NOT joined by chemical bonds. They are easily to physically separate.
