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Force of Superman's Fists

  1. Mar 9, 2008 #1
    Hello there - this is my first time here, and I apologize for my lack of hard knowledge on physics.

    I'm a screenwriter working on a screenplay about Superman. I've always had a love of superheroes (especially Superman), but always wondered about some of the more physical aspects of it. Which brings me to the topic at hand: how hard can Superman punch?

    For the sake of argument, let's assume Superman has the same mass and proportions as a large human, so his fist would weigh about 2 kilos (I believe) and his body would weigh about 100 kilograms.

    Also, assume he's punching someone as durable as he is - say, General Zod, another resident of his home planet of Krypton who boasts the same powers on Earth as Superman. So proportionally to one another, it would be just like two humans duking it out.

    The final step, of course, comes down to the speed his fist can accelerate at. For let's argument's sake, let's do two separate calculations:

    First of all, let's say he can accelerate at one million times the speed of a human, to a million times the velocity. Basically, here his punch is a million times stronger than a human's (I believe) - but how powerful is that? And what is the acceleration and terminal velocity of his fist when it hits Zod?

    Secondly, let's take it to the limit. Say he can accelerate his fist to 99 percent of the speed of light when he throws a punch. How hard does that hit?

    I'm trying to look for bases of comparison for these, so if you could either provide them in Joules - or even better, simply give me analogous incidents of energy production. I'm trying to get a sense of the damage caused to the world around him when Superman gets into a fight. Are we talking 500 pound bomb blasts? Nuclear explosions? Earthquakes?

    Thank you very much - it really means a lot to me.
  2. jcsd
  3. Mar 9, 2008 #2


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    Well, we could start with his classical description: he's stronger than a locomotive, and able to leap tall buildings in a single bound.

    Working through the 1-d kinematics, I estimate to leap the Empire state building in a single bound... if there was no air resistance... if his mass is 100 kg...

    He launches at 93.8 meters per second. (209 miles per hour, or one football field per second)
    His initial kinetic energy is 436 kilojoules
    He (essentially) takes less than 20 milliseconds to jump
    That feat requires 29,000 horsepower
    He exerts 469 kilonewtons of force on the ground
    If his feet take up 1 square foot, that's a pressure of 5 megapascals

    I'm not sure how much damage that would do to the concrete, if any.

    (A quick google search suggests 6,000 horsepower is high for a locomotive engine)
    Last edited: Mar 9, 2008
  4. Mar 9, 2008 #3


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    I'm sure this answer does you little good but:

    Superman's punch is as strong as it needs to be. If you want to concern yourself with at least lip-service to plausible physics, dump DC and start reading Marvel.

    Marvel put out a series of materials many years back (Marvel Universe) describing the vital stats of virtually every major and minor character in its entire universe - including their strength/damage numbers. They measured strength in equivalent pounds (or tons) of TNT.
  5. Mar 10, 2008 #4

    Andy Resnick

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    There's a (reasonably good) little book out there called "Physics of Superheroes" which covers the physics behind many superpowers.

    For example, in order for superman to throw his superpunches, there's an equal and opposite force which acts on superman, meaning he has to somehow plant his feet to stay anchored.
  6. Mar 10, 2008 #5
    Last edited by a moderator: Apr 23, 2017
  7. Mar 10, 2008 #6
    I picked up that book a while ago, and yeah, it wasn't bad. There's also one just about Superman himself that I preferred a bit more, for obvious reasons.

    As for the "equal-and-opposite" force aspect, I always figured he stayed anchored because of his gravity-manipulating abilities. He just subconsciously creates a counter-force with his flight powers that allows him to stand still when he throws those blows.
  8. Mar 10, 2008 #7
  9. Mar 10, 2008 #8
    Superman has to violate conservation of momentum. If not there would be nothing to prevent him from flying of at 400 m/s in the opposite direction of his 20 km/s punch.
  10. Mar 10, 2008 #9
    When watching films and other multimedia entertainment, inconsistencies and glitches bother me, so I am very happy helping you with this.

    Firstly, I would like to point out that beings of the Krypton are made of material not found in the known universe so this greatly complicates things.
    Lets assume that since Superman is a nice guy, in a normal fight he does not use full force in his punches else his foes would explode (not unlike Gears of War) and their remains would be propelled backwards thousands of feet. Lets also assume that your first assumption is wrong, the Man of Steel does NOT have a melee acceleration of .99c. Based on current data, his punches reach a normal human punch speed, and that he is impervious to bullet damage and splash damage but receives minor damage from direct kinetic missile hits. These properties are not unlike some alloys of steel, and along with his supportive nickname, we can deduce that the material Superman is made out of is not unlike an organic alloy of steel. So, when two organic forms of steel collide with sufficient force they will most likely product a crater-like shape similar to that of superheated metal.

    Glad to be of assistance.
    Last edited: Mar 10, 2008
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