Insulated Flask

Overview: There are many ways of making a container that keeps things hot or cold. Silvered films such as the inside of crisp packets can reflect thermal radiation. Black objects absorb radiation and so get hotter if left in the sunshine. Substances that trap air, such as cardboard or bubble wrap reduce heat loss by conduction. Lids and stoppers reduce heat loss by convection.  Evaporation creates cooling which is why sweating cools us down. What is the best combination and how might you find out?

Task: Create a container to keep a substance hot or cold

Equipment Provided: Plastic bottles, cardboard, bubble wrap or other packing material, silvered crisp packets/foil, scissors, tape  Thermometers if available. If they are not then ice can be used to compare how long it takes to melt in the different containers.

Health and Safety: You must carry out your own risk assessment (Rubbish Science accept no liability)  Note: Do NOT use the container for food or drink as it may be contaminated.

Things you might need to know / Questions you might ask:

  • How does trapping air help reduce heat transfer?
  • How can silver and light coloured objects be used to reflect heat?
  • Should we use black materials at all?
  • Why does ‘heat’ rise and how may we reduce heat loss by these methiods?
  • Is it easier to prevent heat loss in bigger or smaller volumes?
  • What combination of materials might work?

Prototyping: Using a thermometer or the time rate that ice melts to compare systems. Explore what combinations of materials seem to be most effective at preventing het loss or gain.

Modifications: Having seen others ideas is there anything you might want to change?

Prediction: How well do you think your container will work?

Do it: How can you ensure it is a fair test. How will you record results?

What happened?: Did your results support your prediction

Tell Someone: Explain what went well and what you think might be improved. Listen to others ideas and decide if they have value.

What did you learn? What do you know now that you didn’t know at the start of the investigation?

Extension/Modify/Do it again: What would you do differently? How can you use the ideas you have learned to solve different problems?

Possible Model – How can you optimise the design?

Overview: There are many ways of making a container that keeps things hot or cold. Silvered films such as the inside of crisp packets can reflect thermal radiation. Black objects absorb radiation and so get hotter if left in the sunshine. Substances that trap air, such as cardboard or bubble wrap reduce heat loss by conduction. Lids and stoppers reduce heat loss by convection.  Evaporation creates cooling which is why sweating cools us down. What is the best combination and how might you find out?

Task: Create a container to keep a substance hot or cold

Equipment Provided: Plastic bottles, cardboard, bubble wrap or other packing material, silvered crisp packets/foil, scissors, tape  Thermometers if available. If they are not then ice can be used to compare how long it takes to melt in the different containers.

Health and Safety: You must carry out your own risk assessment (Rubbish Science accept no liability)  Note: Do NOT use the container for food or drink as it may be contaminated.

Things you might need to know / Questions you might ask:

  • How does trapping air help reduce heat transfer?
  • How can silver and light coloured objects be used to reflect heat?
  • Should we use black materials at all?
  • Why does ‘heat’ rise and how may we reduce heat loss by these methiods?
  • Is it easier to prevent heat loss in bigger or smaller volumes?
  • What combination of materials might work?

Prototyping: Using a thermometer or the time rate that ice melts to compare systems. Explore what combinations of materials seem to be most effective at preventing het loss or gain.

Modifications: Having seen others ideas is there anything you might want to change?

Prediction: How well do you think your container will work?

Do it: How can you ensure it is a fair test. How will you record results?

What happened?: Did your results support your prediction

Tell Someone: Explain what went well and what you think might be improved. Listen to others ideas and decide if they have value.

What did you learn? What do you know now that you didn’t know at the start of the investigation?

Extension/Modify/Do it again: What would you do differently? How can you use the ideas you have learned to solve different problems?

Possible Model – How can you optimise the design?