Heat 1st year
Describe heat energy, its’ units and explain how it converts to other forms
Explain how heat affects expansion and contraction of materials
Explain conduction, convection and radiation
Identify good and bad conductors of heat (insulators V conductors)
Differentiate between heat energy and temperature
Form of energy because it can move things
- E.g: Makes a hot air balloon rise.
- Steam engines
Measured in JOULES (J)
Sunlight (heat) is used by plants for Photosynthesis (to make food), it is converted to chemical energy.
Oil and gas are burned in power stations to produce heat energy, this is used to turn turbines which produce electricity (electrical energy)
The movement of particles/molecules produces heat
Particles move about more and take
up more room if heated – this is why
things expand if heated
It is also why substances change form when heated
solids liquids gases
Heat always moves from a warmer place to a cooler place.
Hot objects in a cooler room will cool to room temperature.e.g: tea, coffee
Cold objects in a warmer room will heat up to room temperature.e.g: butter, ice
What do you think?
How does heat energy get from the Sun to the Earth?
There are no particles between the Sun and the Earth so it MUST travel by radiation
The transfer of heat in rays, from a hot object, without needing a medium to pass through
It travels in all directions from a hot object
The hotter an object is, the more heat it will radiate out
Does the surface affect the way heat is radiated?