Energy Flashcards
What is work done
The energy transferred when a force is used to move an object a certain distance
What is work measured in
Joules (J)
How do you calculate work
Work done (J) = force (N) x distance moved (m)
What is a force multiplier
uses a smaller input force (what you apply) to to generate a larger output force (what is created)
What happens when you increase the distance from the pivot
The less input force is needed to be used for the same output force as before
What is radiation
A method of transferring energy without the need for particles
Name an example of radiation
Thermal energy being transferred from the sun to us through space
What is infrared radiation
a type of radiant energy that’s invisible to human eyes but that we can feel as heat
do darker matte surfaces absorb infrared radiation and why
Darker surfaces absorb more infrared radiation because lighter colours reflect light instead of absorbing it
do shiny and smooth surfaces absorb more infrared radiation
Shiny surfaces absorb and emit less infrared radiation and instead reflect it
What is a thermal imaging camera
The amount of infrared radiation being emitted can be viewed on a thermal infrared imaging camera
What gives off more radiation hotter or colder objects
Hotter
what happens to particles when they are heated
They move quicker
What has more thermal energy a bath of water at 30 degrees or a cup of tea at 90 degrees
A bath of water as there are many more particles
Define conduction
The transfer of thermal energy by the vibration of particles happens mostly in solids because the particles are close together
What does high thermal energy store mean
High temperature
Why are gasses and liquids poor conductors
Because their particles are spread out and do not collide often
What is convection
The transfer of thermal energy in a liquid or gas
What is a convection current
When the particles near the heat source are heated the spread out and rise as they are less dense the more dense particles will take their place by the heat source creating a flow of particles
Name some energy stores
Kinetic (movement ) anything that moves has a kinetic energy store
Magnetic energy store two magnets that attract or repel have energy in there magnetic energy stores
Elastic energy store anything stretched had energy in its elastic energy store like rubber bands
How can u transfer energy between stores
Mechanically
Electrically
By heating
Name an example of energy being transferred between stores
When you burn fuel, energy is transferred from the fuel’s chemical energy store to the thermal energy store of the surroundings
What is energy measured in
Joules (J)
When is energy transferred
When a force moves an object
How do you calculate energy transferred
Energy transferred (J) = force (in newtons N) x distance (in meters M)
How does heat travel
From hot to cold
What is thermal equilibrium
A point at which both objects are the same temperature
Do the objects need to be touching for energy transfer in solids
Yes
What are materials that transfer energy by heating quickly called (like metals)
Conductors
What are metals that transfer energy more slowly called (like plastics)
Insulators
