Heat In Jars
If different brands of food jars have different prices, then the most expensive one should do the best job because their design is probably more efficient than the others.
How Do Food Jars Keep Food Warm?
They use stainless steel for the inner and outer wall .
The hot air in the food jar can bounce off the steel inner wall and won’t escape.
The outer wall bounces cold air off the outer wall so the cold air dosen’t go in.
Vacuuming the air out of in between the inner and outer walls prevents transfer of temperature from inside to outside.
MANIPULATED: Different brand food jars (prices difference)
Same volume of each jar
Same temperature of the water put into the food jars
Same amount of water in the 4 jars
Same time I waited for the water to cool
RESPONDING: the temperature of the water after 5 hours
Collect background research
Pour same temperature and amount of water in the 4 food jars
Wait 5 hours
Repeat steps 5-10 two more times
Analys + make conclusion
“Thermos” (1) kept in 62.4°C of heat after 5 hours.
“Navaris” (2)kept in 61.6°C of heat after 5 hours.
“Goodful”(3)kept in 57.3°C of heat after 5 hours.
“slm”(4)kept in 60.7°C of heat after 5 hours.
“Thermos” (1) kept in 63.2°C of heat after 5 hours.
“Navaris”(2)kept in 61.5°C of heat after 5 hours.
“Goodful”(3)kept in 57.6°C of heat after 5 hours.
“slm”(4)kept in 61.4°C of heat after 5 hours.
“Thermos” (1) kept in 62.8°C of heat after 5 hours.
“Navaris”(2)kept in 61.3°C of heat after 5 hours.
“Goodful”(3)kept in 56.6°C of heat after 5 hours.
“slm”(4)kept in 60.0°C of heat after 5 hours.
I thought that the most expensive one would do the best, but it actually was the one with the highest popularity.
The test results show that after 5 hours,
jar(1) was able to keep in 62.4°C as an average,
jar(2) was able to keep in 61.4°C ,
jar(3) was able to keep in 57.1°C,
jar(4) could keep in 60.7°C.
The most expensive jar may not do the best job.
Instead I noticed that the jar with higher popularity worked better.
If I were to make my project bigger, I would see how long the food jars keep warm until the food gets cold. I would also find a way to make food jars more effective so it keeps more heat/cold in during this time.
Sources Of Error
A source of error is when I was pouring water into the jars, a few drops might have fell out. It makes the amount of water in each jar be different. It may affect the experiment result.
Also, during the time I was closing the lid, some heat might have escaped from the jar.