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HEAT EXPERIMENT #5

Start and end each session with a visible thinking learning task - what I used to think and what I think now - to help implement the Five Formative Assessment Strategies to improve student learning.

Learning Tasks That Elicit Evidence of Learning 1)

Open your Science book/Journal and briefly write down the title, date:

  • Title: HEAT Experiment 5
  • Date: xx/06/2018

Please spend ten minutes to write down what you think about each of the statements below (you may use drawings/images or refer to other sources of information). For each question, explain why you think your answer is correct.

  1. What do you think is most likely to have more heat - candle burning on an ice-cream birthday cake, or the ice-cream cake?
  2. How does heat move along a metal ruler?
  3. Can you tell how much heat energy something has by measuring how hot it is?
  • Draw a line right across the middle of the page (below your answers).

At the end of this session, you will have another chance to think about and write down your answers to the same three questions.

Why we focus on 'understanding the principles' rather than on 'learning the facts'

Michio Kaku

  • “We need less memorization - I never memorized the periodic table of the elements - I've never used it, and I'm a physicist! I can look it up” Michio Kaku - 2)
  • If your teaching/learning focuses on an understanding of the principles, you don't need to remember the facts - just look them up. No matter how many facts you remember, there is no guarantee that you will ever understand the principles that underly them.
  • All that you need to understand about the current scientific view about heat is….

Everything in the universe is made up of matter and energy.

  • “The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together” 3)
  • Matter is made up of atoms and molecules (groupings of atoms).
  • Energy causes the atoms and molecules to always be in motion - either bumping into each other or vibrating back and forth.
    • The motion of atoms and molecules creates a form of energy called heat or thermal energy which is present in all matter. Even in the coldest voids of space, matter still has a very small but still measurable amount of heat energy.
    • Energy can take on many forms and can change from one form to another.

In summary, put energy into a system and it heats up, take energy away and it cools.

  • Heat can be a chemical or physical phenomena but all chemical phenomena ultimately reduce to physical phenomena (physics)
  • Thermal energy itself can cause a substance to heat up, simply by increasing the speed of its molecules. For example, when we are cold, we can jump up and down to get warmer. If we stop moving, we cool down. 4)


The only five things you need to understand about heat & temperature

Heat versus temperature

How heat energy can transfer



Video. Bill Nye - Heat (2min)



Video. Bill Nye - Conduction, Convection & Radiation (2min)


1. Conduction experiment:

Image: How heat travels along a spoon

Conductivity


2 Convection Experiment

Video. Convection Currents 2 (2min)

MATERIALS

This is a new experiment showing how heat moves from one place to another via convection.

HYPOTHESIS:

METHOD

  1. Place a cup of iced water under the left hand side of the water tank
  2. Place a cup of hot water under the left hand side of the water tank
  3. Mix some red food colour into a small cup full of room temperature water
  4. Mix some blue food colour into a small cup full of room temperature water
  5. Fill one pipette with red food colouring drawn from room temperature coloured water
  6. Fill one pipette with blue food colouring drawn from room temperature coloured water
  7. Carefully squeeze blue colour into the bottom of the tank - The cold/left side of the tank and red into the hot/right-hand side
    1. Slowly continue to fill pipettes and release more food colouring into the water tank

DISCUSSION

3. Infrared Radiation experiment

An infra-red (IR) thermometer can be used to help make some experiments more concrete.

Other types of energy that convert into thermal energy can be inferred from thermal signals. Hence, many invisible physical, chemical, and biological processes that absorb or release heat can be visualized, discovered, and investigated. The following experiment can be successfully performed using a simple IR thermometer only.

An IR Trap (The Greenhouse Effect)

Greenhouse Effect Shine a desk lamp (or invisible IR light source) through an inverted plastic take-away or similar container.

The light will be absorbed by the black paper inside.

The paper will radiate IR light, but the IR radiation emitted from the paper cannot penetrate through the transparent container.

As a result, heat is trapped inside the inverted container.

The above can be measured using an IR thermometer.

QUESTIONS

Source - See Global Warming Experiment


Video. Radiation Fog (2min)

Radiation Fog forms when a layer of warm, wet air forms close to the ground and another layer of cooler, drier air forms on top of the warmer layer. When the ground begins to cool down, the water droplets in the warm, wet air begin to condense to form fog. This type of fog is called radiation fog.

Fog will form in one of the bottles – make a prediction based on the description of how fog forms on which bottle will produce a simulation of fog. Which one do you think will produce the fog?

MATERIALS

Estimated Experiment Time - One to two hours at most.

PROCEDURE

  1. Empty the soda bottles and rinse them out thoroughly. Label each soda bottle, one with “Cold water” and the other with “Hot water.”
  2. Fill the first soda bottle ¼ of the way full with cold water. Place an ice cube in the neck of the soda bottle so it is wedged in but does not pass all the way through the bottle. What happens? Record your findings in your journal.
  3. Repeat step two with the second soda bottle, only this time, filling the bottle ¼ of the way full with hot water. Place the ice cube in the neck of this soda bottle and note what happens.

Note - This experiment is an accurate simulation of radiation fog.

OBSERVATION


Back to where we started

We started our study of HEAT on this page.

Here were some of our first questions:

  1. Are some materials warmer or colder than others?
  2. What is the difference between 'hot', 'cold' and 'heat'?
  3. Does the temperature of something depend on it's size (a small versus a large ice block)?
  4. How does heat move from one object to another?

Thinking about what you have seen over the last few weeks, do you think you have you changed any of your ideas about these questions?


BEFORE END OF SESSION (allow 10 minutes)

Learning Tasks That Elicit Evidence of Learning 5)

At the end of this session, write down new answers to the same three questions you answered earlier:

  1. What do you think is most likely to have more heat - candle burning on an ice-cream birthday cake, or the ice-cream cake?
  2. How does heat move along a metal ruler?
  3. Can you tell how much heat energy something has by measuring how hot it is?
  • Have you changed your mind about any of the answers you gave at the beginning of the session?

Extension Activities

REVISION - Does 'heat rise' and/or 'does hot air really rise'?

  1. 'Does hot air rise (due to heat)' or does 'cold air fall (due to gravity)'?
    • When you have two theories to explain the same thing, what can you do
    • To test a theory, design an experiment where each theory predicts a different outcome.
    • In the space station, there is plenty of air but almost no gravity.
    • If hot air rises, then it should also 'rise' in zero gravity. Does it?
    • High above our planet in the realm of satellites and space stations, the familiar rules of Earth do not apply. The midday sky is as black as night. There is no up and no down. Dropped objects do not fall, and hot air does not rise.6). In the absence of gravity, there is no buoyant force so no movement is possible physically but however hot air will start exchanging heat with the cooler air by means of conduction and radiation if they are in contact with each other and only by pure radiation if they are not in contact. ( no convection can takes place because of the absence of gravity) 7)

Video: Convection in zero gravity (2min)


Video: Gravity - The curved fabric of space time (4min)


Video: Relativity - The fabric of space time (2min)


Video: Gravity - The fabric of space time (5min)


</WRAP

Exploratorium Science Snacks


2. Convection experiment:

Video. Exploratorium - Convection (3.5min)

Visualize the fluid motion of convection cells. This phenomenon occurs all around us but is usually unseen. For this activity, all you need is soapy water, a heat source, and some food coloring—the effect caused by the rising and sinking fluids is spectacular. Full instructions for doing this activity on your own are available at: http://www.exploratorium.edu/snacks/p….


Video: Exploratorium (Bruce Yeany) - Heat & Radiation (4min)

  • IF UNABLE TO ACCESS YOUTUBE, TRY:Viewpure

READ MORE...

  • Concord 'InfraredTube' Concord InfraredTube provides resources that use affordable IR cameras to visualize invisible energy flows and transformations in easy-to-do science experiments… making thermal energy more readily “seen”.


Helio-centric versus Helical Motion Of Our Solar System (4min)

  • IF UNABLE TO ACCESS YOUTUBE, TRY:Viewpure


References