What is heat? What is the unit of heat? What is temperature? What are the units of temperature?
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Transcript of What is heat? What is the unit of heat? What is temperature? What are the units of temperature?
8I HEATING AND COOLING
HEAT AND TEMPERATURE
What is heat?
What is the unit of heat?
What is temperature?
What are the units of temperature?
COOLING
Heat water in a beaker to 60°C Remove the beaker from the heat and
record the temperature every minute until it reaches 40°C
Put your results in a table Draw a line graph
LINE GRAPH CHECKLIST
I have Used mm graph paper Written a title Underlined the title with a ruler Drawn the axes with a ruler Put the independent variable on the x axis and the dependent variable
on the y axis Labeled the axes Labeled the axes with units Used a regular increase on the axes (e.g. 2,4,6 NOT 1,3,4,7) Used crosses for the data points Drawn a line of best fit (curved or straight)
CONCLUSION
What happened to the temperature over time?
Where did the heat energy go? How could you speed up this process? How could you slow it down?
HEAT AND TEMPERATURE RECAP
heat and temperature game
TEMPERATURE ESTIMATIONMy estimate (°C)
Real temperature (°C) Difference (°C)
FridgeFreezerClassroom Tap waterHot coffeeMy handOutside todayLondon todayMy armpitHot bath/shower 44 Heated swimming pool 28 The sea in summer 22 The sea in winter 13 The Caribbean sea 26 The Arctic sea -1.5 Bunsen burner safety flame 300Bunsen burner blue flame 700
HEATING
What happens to solids, liquids and gases when you heat them?
What happens to the particles when this happens?
EXPERIMENTS
CONVECTION
What is a convection current?
In which 2 states of matter does convection happen?
Convection experiment1. Place about 400mls of
water into a beaker and place on a tripod stand.
2. Start to heat the water with a bunsen burner (blue flame).
3. Carefully drop the coloured crystal into the beaker so that it is seating at the bottom of the beaker. Watch what happens.
www.abernet.org.uk
Convection experiment
Complete the diagram to show what happened.
Convection currents can be found when liquids are heated for cooking.
Convection currents in liquids
drinkmatron.com
Draw the particles and explain what happens at each stage in this convection current.
CONDUCTION AND INSULATION
What is conduction?
Name 2 good conductors
Name 2 good insulators
YOU ARE GOING TO INVESTIGATE WHICH METAL IS THE BEST CONDUCTOR
Write the Aim, Prediction, Variables, and prepare a results table.
HOMEWORK
Graph (bar chart) and conclusion
CONCLUSION The pin fell of the metal that is the best
conductor of heat first.
Make a list of the metals from best conductor to the least conductor
CONDUCTION 2
Which direction does heat ALWAYS move in?
Describe what happens to the particles when a solid conducts heat.
Why are gases bad conductors of heat?
WHY DOES YOUR HAND FEEL COLD IF YOU HOLD THE SPOON?
CONVECTION RECAP SHEET
WATER TEMPERATURE DEMO
WRITE AN EXPLANATION FOR YOUR CONVECTION DIAGRAMS
CONDUCTION DEMO
WORKSHEET
INSULATORS Materials which are very poor
conductors are called ‘thermal insulators’
Wood, cotton, cork and expanded polystyrene are good insulators
CONDUCTION How well a material conducts heat
depends on how close the particles are together… Solids are the best Then liquids Gases are terrible conductors of heat
Design a Saucepan Challenge
Which parts of the saucepan do you want to get hot and which bits do you want to keep cool?
Why?
Base
Main part of pan
HandleHolder on lid
RADIATIONRADIATION Which direction does heat move in by radiation?
Can radiation go round corners? Why?
Give 3 uses of infra-red radiaton
HOW DOES HEAT ENERGY GET TO US FROM THE SUN?
• Heat energy from the sun travels to earth by radiation.
• Since the space between the sun and the earth is a vacuum (no particles present), the heat cannot travel by conduction or convection.
Infrared Radiation
AIM: TO INVESTIGATE RADIATION IN BLACK AND SILVER FLASKS
Prediction:
Variables: Independent: Dependent: Control:
• Heat energy waves (or rays) are known as Infrared Radiation.
• Infrared Radiation waves will travel out from a hot source in all directions.
Heater
Infrared Radiation
INFRA RED RADIATION 2
Which colours absorb more infrared radiation?
Which colours reflect more infrared radiation?
Which colours emit more infrared radiation?
• Special Infrared cameras can be used to show the Infrared radiation given off by different things.
Infrared Radiation pictures
gosublogger.com
• This is a infrared image of a child’s hand holding a lizard.
• Lizards are reptiles and are cold blooded.
• Notice how the child`s hand is warm compared to the lizard.
Infrared Radiation pictures
• This is an infrared image of a person.
• What area is the hottest?
• What do you think it is?
Infrared Radiation pictures
This is an infrared image of two coffee cups containing very hot drinks.
INFRARED RADIATION PICTURES
INFRARED RADIATION PICTURES
This is a infrared image of a dear in the dark.
Since infrared cameras detect heat radiation they can see the heat from warm blooded animals in the dark.
This infrared medical scan shows an injured and healthy leg.
The bright white region shows the location of the injury, which is warmer due to the increased blood flow to the injured area.
INFRARED RADIATION PICTURES
This is a infrared image of footprints.
As this person walks away barefoot the heat left behind her feet stills glows on the ground.
INFRARED RADIATION PICTURES
This is an infrared image of a cat.
The yellow areas are the warmest and the purple areas are cool.
INFRARED RADIATION PICTURES
This is a infrared image of a tyre that has been heated by friction with the road.
Notice how the area of the tyre that touches the road glows much more brightly when you look through the infrared camera.
INFRARED RADIATION PICTURES
This is a infrared image of a zebra.
Notice how the stripes appear on the infrared.
Do you think these are the black or white stripes?
INFRARED RADIATION PICTURES
This is an infrared image of a heating element.
Even after the stove is turned off, this heating element will glow brightly in the infrared until it reaches room temperature.
INFRARED RADIATION PICTURES
Infrared Radiation pictures
This is a infrared map of global sea surface temperatures.
Infrared satellites are used to measure and track changing ocean surface temperatures to help predict weather patterns.
Infrared Radiation pictures
RADIATION EXPERIMENT
Aim Prediction Variables Method
CONCLUSION
ConclusionLevel 3 Level 4 Level 5What did you find out?Describe the pattern.
Use number examples
Explain. Use scientific vocabulary.
EVALUATION
EvaluationLevel 3 Level 4 Level 5Suggest improvements
Improvements and reasons
Evaluate the effectiveness.Explain differences in repeats.
TEMPERATURE CHANGE IN CHANGES OF STATE
What happens to the particles when a solid changes to a liquid?
What happens to the particles when a liquid changes to a gas?
What happens to temperature when a substance is changing state?
MELTING ICE PRACTICAL
Measure the temperature every minute until there is no ice left.
HEAT TRANSFER POSTER
Make a poster to show and explain all the methods of heat transfer in one of these situations: The beach The kitchen Formula 1 cars A vacuum flask
This will be assessed formally for AF2
CONCORDE WEBSITE
http://www.travelscholar.com/concorde/page03.html
ASSESSED PRACTICAL
You are going to investigate insulation This will be assessed on AF3, 4 and 5