Energy transfer test Flashcards
What is energy transfer?
the movement of energy from one place to another
What is conduction?
the transfer of thermal energy between solids
How does conduction work?
when two objects are touching, the hotter object will transfer heat to the colder object. Particles in the hotter object move more and have more kinetic and thermal energy. As particles in the hotter object collide with the cooler object, they pass on some of their kinetic energy until they are both the same temperature.
What is a conductor?
materials that allow heat or electricity to flow through them easily because they have electrons which can freely move around to transfer the energy around
What is an insulator
materials that do not allow heat to transfer through them easily
What is convection
heat transfer between fluids because of differences in density
how does convection work
heat causes particles to spread out becoming less dense so they rise. as they cool they condense and fall creating a cyclical pattern
what does a transverse wave look like and an example
waves, electromagnetic
what does a longitudinal wave look like an an example
dots/lines (slinky being stretched and pulled away), sound + seismic
what are transverse waves
the direction of the wave is at right angles to its oscillation.
what are longitudinal waves
when particles oscillate (go back and forth) in the same direction as the way the wave is travelling.
what do sound waves do
compress air molecules together, then stretch them apart (rarefication)
lower frequency is…..
lower notes
higher frequency is…….
higher notes
can sound pass through a vaccum
no, it needs a medium
what mediums do sound move faster through
the denser the medium the faster the sound can travel
why does sound move faster through dense materials
because it can go straight through as the particles are connected, when they are spread out it has to jump around to get to each particle
what can light do
reflect, refract (bend)
what is frequency
how many waves pass in a certain time
what is frequency measured in
hz
can light pass through a vaccuum
yes
which colour has the longest wavelength
red
what colour has the shortest wavelength
violet
why do objects seem coloured
because they reflect the colour that they are and absorb the others
