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Just around everyone has used rubber bands, but couple of people have taken the time to observe the less apparent properties the these day-to-day objects. In this task you will research the heat properties that rubber, that is, the actions of rubber as it relates come heat, a type of energy.

You are watching: Does temperature affect the stretch of a rubber band

In the very first experiment you will attempt to detect heat flow into or out of a rubber band. To execute this,you require a quite sensitive heat detector. Fortunately, you have actually such a detector with you at every times.Surely, you"ve feel the warmth of a fire or the cold of an ice cube. Therefore, you know that her skin issensitive to warmth flow. In this experiment, you will certainly detect heat circulation using few of your many sensitiveskin, that on your forehead or on your lips.

Place your thumbs with the heavy rubber band, one on every end. Without extending the band, organize it to her forehead or lip. Does the band feeling cool or heat or about the very same as her skin? Repeat the test several times until you space sure that the result. move the rubber band slightly away from your face, so that is not emotional your skin. Conveniently stretch the band around as far as you can and, holding the in the extended position, touch it again to her forehead or lip. Walk it feel warmer or cooler or around the exact same as the did when it was relaxed? relocate the extended rubber tape away from girlfriend face. Quickly let it relax come its initial size and again organize it to her skin. Does that feel warm or cool? Repeat the stretching and also testing, and relaxing and testing several times until you are sure of the results.

An thing feels cool or cold come you when warm flows from her skin to the object. Conversely, an object feels warm or hot when heat flows from the object right into your skin. If the extended rubber band feels cool, climate it absorbs warmth from your skin. If that feels warm, climate it gives off warmth to your skin. If the tape feels neither heat nor cool, then there is no detectable heat flow. This three instances can be stood for as follows:
Case 1. calm Band + warmth extended Band Case 2. tranquil Band extended Band + warm Case 3. calm Band extended Band (No Heat)
Which the these three cases ideal describes what friend observed?
There is another way to check which the the 3 statements is correct. We deserve to see what wake up to thelength that a rubber band if we warmth or cool it.
hang one finish of the rubber band from the wall surface or ceiling and suspend a load from the other end of the rubber band. (What you usage for a load will rely on what is available. The weight have to be heavy enough to stretch the rubber band, but not so heavy that the is most likely to rest the band. Because that example, hang the tape over a door knob and also suspend a hammer native the band.) heat the rubber band through a hair dryer. Start the dryer and, when it has warmed up, rotate its heat on the stretched rubber band. Go the extended rubber band become longer or much shorter when that is heated?
Does this monitoring agree with what you found in the an initial part of the experiment? doing an experiment number of ways and also checking for commitment in the outcomes is an essential strategy in science.

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When rubber is heated it behaves differently than most familiar materials. Most products expandwhen they space heated. Take into consideration the fluid in a thermometer. The thermometer works since the liquidexpands when its temperature increases. Similarly, a cable made the metal, such together copper, i do not care longeras it gets hotter. The growth of metals with increasing temperature is the rule behind thefunctioning of home thermostats and of jumping discs.
Whether a material increases or contracts when it is cook is largely a due to the framework of the molecules it is do of. When power is added to a material, that is dispersed throughout the product and, ~ above average, every atom or molecule will certainly have much more energy and also will it is in moving an ext energetically 보다 it was before the energy was added. In materials made up of small, compact molecules, e.g., the liquid in a thermometer, together the molecule move around more, they push their neighboring molecules away. Rubber, ~ above the various other hand, contains very large, threadlike molecules. As soon as rubber is heated, part of the molecules move about an ext vigorously. In order for one component of the molecule to move an ext vigorously together it is heated, it should pull its surrounding parts closer. To visualize this, think of a molecule of the extended rubber band together a item of string laid out right on a table. Heating the stretched rubber band causes segments the the molecule to move more vigorously, which have the right to be represented by wiggling the middle of the string earlier and forth. As the middle of the string moves, the ends of the string get closer together. In a similar fashion, the end of the rubber molecules acquire a little bit closer together the rubber is heated, leading to the extended rubber tape to contract.

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After Prof. Shakhashiri prove this experiment in one of his live shows, one attendee sent him this picture. "The youngsters grabbed rubber bands as soon as they gained home, to endure the warmed-when-stretched phenomenon."
For additional information, see CHEMICAL DEMONSTRATIONS: A Handbook because that Teachers of Chemistry, Volume 1, by Bassam Z. Shakhashiri, The university of Wisconsin Press.Back to residence Experiments