Heat Flashcards
(17 cards)
Celsius scale
A temperature scale that follows the melting point for ice as 0 and the boiling point for water as 100
Kelvin scale
Starts at absolute 0 (-273.15) the point where particles stop moving
Temperature
The amount of kinetic energy within the particles of a substance
Absolute zero
the lowest temperature possible at which the particles stop moving
Thermostat
a device that automatically regulates temperature
Thermometer
an instrument for measuring the kinetic energy within a substance
Radiation
Heat transfer through electro magnetic radiation
Conduction
Heat transfer through touch
Particle theory: Quick moving on particles come into contact and cause slower moving particles to increase in speed
Convection
Heat transfer through a fluid
Why does a frying pan usually have metal bottom and sides and a wooden handle?
Because metal is a good heat conductor and wood is a.l good insulator so the food will cook as the heated pan transfers the heat to the food while the wood handle won’t conduct much heat so you don’t burn yourself.
How does an oven use radiation
The food and pan absorb the heat by the heat waves caused by the heat source
How does an oven use conduction
The pan absorbs the heat then transferring it to the food
How does an oven use convection
The oven creates a convection current with the heat from the heat source
Where should a pool heater be placed to heat the pool best
A pool heater should be in the centre on the floor so it will create a convection current as the cool water goes down and the warm water goes up.
Rank these conductors from best to worst
Glass, stainless steel, plastic, styrofoam, wood, copper, wool, rubber
Copper, stainless steel, glass,
plastic, rubber, wood, styrofoam, wool
What happens when water heats from -5 degrees to 105 degrees
At -5: the particles are vibrating and bonded to one another can’t move
At 0: the water starts to melt bonds loosen less attracted and start to move
At 75: water heats there is more kinetic energy as the particles move faster
At 100: water starts to evaporate kinetic energy builds as particles move faster bonds break and particles move freely
At 105: has become a gas and particles move freely
Why shouldn’t you put a pan with a wooden handle inside an oven and what else could be used instead of wood
You shouldn’t put wood in the oven because it can easily catch on fire but if you have a metal handle and wear gloves because metal is a heat conductor
