Put it in hot (but not boiling) water for a minute or two, then take it out and rest something heavy on top of it until it cools. It should be better if not perfect then.
If it is plastic one there really is no way to fix it. But, if it is metal but it close to boiling water for around two to three minutes. Then take your slinky out (Put it in a uncoiled and stacked form.) and let cool with a heavy book on top of it and then your slinky should return a mostly normal stage.
The strings in a regular slinky is metal.
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The metal on a slinky is considered a medium for transmitting mechanical waves. When a disturbance is applied to the slinky, it creates compressional and rarefactional waves that travel along the metal coils. This allows the wave energy to propagate through the slinky from one end to the other.
A slinky toy can conduct electricity because it is made of metal, which is a good conductor of electricity. When a voltage is applied to the slinky, the electrons in the metal can move freely, allowing the electricity to flow through it.
If a slinky is tangled or bent out of shape, you can try gently pulling and twisting it back into its original form. If the slinky is broken or stretched out, it may be difficult to repair and you might need to replace it. Regularly untangling the slinky after use can help prevent it from getting damaged.
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A standard metal slinky typically weighs around 3 ounces. However, this can vary depending on the material and size of the slinky.
A slinky is made of metal or plastic and functions as a mechanical toy that moves in a spring-like manner when pushed or pulled.
To fix a metal slinky that is tangled or deformed, try gently pulling and stretching it out until it returns to its original shape. It may take some patience and manipulation to get it back to its original form, but be careful not to bend or kink it too much as this can cause permanent damage. If the slinky is heavily tangled, you can try gently twisting and turning sections of it to help untangle it.
You can throw it away and buy a new one.
The density of a metal slinky depends on the specific metal it's made of. Typically, metal slinkies are made from materials like steel or aluminum, which have densities ranging from 2.7 to 7.8 grams per cubic centimeter.