Captain America:

After not meeting physical requirements to enlist into the army, Steve Rogers was offered the opportunity to volunteer in a project to create soldiers that were in pristine physical shape.  This is where the science of Captain America takes the back seat to the storytelling; Rogers is given a serum that
completely alters his scrawny frame into an ideal physique.

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Although real-life science cannot accurately explain how Rogers' transformation is possible, physics can somewhat explain Captain America's iconic item: his shield.  The mystery of his shield comes from our knowledge of the First Law of Thermodynamics.  It is known that energy can be changed from one form to another, but cannot be created or destroyed.  The questioning occurs because when Captain America uses his shield to protect himself from a major blow such as a punch from Hulk, he remains completely unfazed.  In The Avengers, when Thor's hammer met Cap's shield one can see where the energy of the collision transfers.  This, however, is an exception; throughout the comics and other media collisions with Captain America's shield appear to cause a loss of energy.

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Now, it is known energy can not be destroyed, so one must assume the energy is being absorbed by the shield.  To make this possible, Captain America's shield is made of a one-of-a-kind alloy of steel and vibranium.  Marvel authors created vibranium as an element found from a meteor shower.  They created this element to explain his shield acting as a super-capacitor.  The shield can hold large amount of power like a battery, however, it's "charged" almost instantly like a capacitor, which explains where the energy goes during collisions.  So even though the reality of there being a shield such as Captain America's is not quite possible, there is some scientific proof, albeit a small amount, to draw the audience away from the fictitious aspects of the story.

Home Page

Captain America

Spider-Man

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The Flash

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Bibliography