Clark Kent's Super Powers
Clark's powers are powered up by Sun in our Solar System, turning his own body into a large solar battery. Apparently, not only can the Sun powers him up, it can also cause Clark to go haywire as well, as seen in "Perry" (Season 3, Episode 5). Since his body is one large battery, the solar energy which he stores up, as we speculate, has to be channeled out in some ways, namely his powers.
But the Sun is not the only that is capable of interfering his powers. The radiation from Kryptonite, the meteor rocks that fall with the spaceship from the sky is also capable of rendering him powerless. Its effects vary with the amount of time Clark spends near it. The milder side effect of the radiation renders him weak and makes him unable to focus his energy to use his powers. The worst case scenario when Clark is exposed to the meteor rocks for too long is death.
In the first season premiere, when Jonathan and Martha Kent found little Clark in the fields the day the Kryptonite meteor rocks hit Smallville, Clark did not possess all the powers that made him legendary. Rather, he only received a fraction of it, as his powers only starts to grow during his adolescence years. This leads us to what, exactly, are his powers and the extent of his powers.
Super Strength
Another power that seems to be the base for his other powers, Clark's super strength is one thing that helped him a lot from time to time, other than his invulnerability. It was believed that there is a connection between his invulnerability and super strength, although the link between these two powers is very weak. Indeed, these two powers has been so assimilated that it is often difficult to distinguish between the both of them correctly.
Clark has this power ever since the premier of the series. It was featured as soon as Clark stepped out of the space ship. He used his gifts to help the Kents got out of the over-turned truck, which is described in "Arrival" (a book based on the episode "Pilot" by Michael Teitelbaum) as "tearing the door away in one swift move, as if he were unwrapping a birthday present".
This casual display of strength lead us to believe that the Sun must have powered Clark up, turning him into an ant that is capable of carrying objects up to thirty times its own weight. Since this ability is untested, it is highly possible that Clark is capable of doing even more. We have seen how he is able to smash metals to bits without injuring himself, protect people from fire blasts and fast moving vehicles without a scratch, got hit by Lex's car and survived. Therefore, we are not surprised if his super strength shot into un-chartered area.
Invulnerability
This is marginally more interesting power and is perhaps, the base for all of his other powers. Unlike what most people believe, this power actually comprises of two components. The actual invulnerability, where his skin is even thicker than a hide, protects him from physical harm, thus allowing him to do just about anything he wants. The other component is actually the natural bio-electric aura he possesses, which also has limited force field properties protecting skin-tight clothes. This includes his costume he wears in the future.
Apparently, this power grows and develops with him through his adolescence years. In "Tempest" (Season 1, Episode 21), a clueless Clark was involved in an explosion of his truck rigged by a rogue reporter to test him. Following the accident, he related to the Kents how he "barely felt the heat this time, and the debris left no bruises". In other words, we can draw the assumption that when he was younger, he could still feel a substantial amount of pain and that he bruise, although it is probably not obvious to many.
But what is more interesting to us is, to what extent does this power affects him? If he does not feel the pain that was caused due to collision etc, then theoretically, he should not be able to feel anything when someone touches or pats him, like what Pete always do. So our views on this matter are that, the invulnerability he possesses probably has a limit to the amount of force directed at it. A parallel example would be a rubber band that has elasticity. Once beyond that limit, the rubber band would snap. In Clark's case, when beyond a certain limit, his invulnerability automatically comes into play to protect him from harm.
But apparently, this invulnerability does not confine to physical. It also includes mental capabilities. In "Stray" (Season 1, Episode 16), when Ryan attempts to read Clark's mind after asking him what he wants for breakfast, he got a blank from Clark. Our response to this is that, Clark's invulnerability does not confine itself to physical protection, but also mental protection as well. This raises two interesting issues though. Should there, one day, be an X-Men and Smallville crossover, what would happen if Wolverine AKA Logan's indestructible adamatium claws or the world's strongest telepath Professor Charles Xavier's telepathy are used against Clark? Would the adamatium claws and telepathy still work against him? Or would Clark's invulnerability still hold?
Super Speed
While many of you think that super speed is actually a power of its own, we beg to differ. We would like to argue that the super speed is actually a result of the fusion of his super strength and the two components of his invulnerability.
Generally, on Earth, the only source that can move at such a high speed is light. But the reason why light is able to move at such a high speed is because of its negligible mass. In fact, light is a wave, which has no mass at all. This means, in order to travel fast, you should have as little mass as possible, so the gravitational force of Earth acting on you would also be negligible.
Similarly, for Clark's case, the factor that contributes to his ability to defy gravitational force acting on him is his bio-electric aura. Apparently, if this aura can, to some extent, allow him to ignore the gravitational force acting on him, then he would be considered weightless. That would account why he is able to ignore the gravity. So when he runs, the only force is his legs that are propelling him forward.
That leads us to his super strength. As a person run, the how fast he ran depends on the amount of power or energy he has in his leg. Meaning to say, the stronger a person's leg, the faster he can speed off. In Clark's case, the reason why he is super speed is because of the super strength he possesses in his body, including his legs. In other words, his super strength allows him to run at a faster pace, and since his strength is untested and possibly unparalleled, there is a possibility that his speed is unlimited too.
But there is one problem. If an object of significant mass travels at high speed, there is a high probability that it will disintegrate altogether due to air resistance. The air resistance is NOT cancelled out because of his bio-electric aura, but because of the physical property of his invulnerability. Since the force of the air resistance acting on him is high, it is highly possibly that his invulnerability limit (For more information, please refer to the Invulnerability section) is triggered off and the physical property of his invulnerability protects him from the air resistance, hence effectively protects him from disintegrating.
X-Ray Vision
In contrast to what many people believe, heat vision and X-ray vision are actually related. It is just that they are of different spectrum. The electro-magnetic spectrum is actually of many different light waves, and our eyes are only capable to capturing the visible light, a very small range which allows us to see colors. However, Clark's eye is different, as it seems that he is capable of not just capturing the visible region, but also the regions where our normal eye is unable to capture. These include X-ray and Gamma-Ray region.
The X-ray vision enables him to see through all substances except for lead. He first got that power when he trying to help Lex to solve a crime in "X-ray" (Season 1, Episode 4). So somehow, during that phase, his X-ray vision is triggered, although it is not discussed at a deeper level. Our conclusion is that, perhaps, in his eyes, there are many different "lenses", and X-ray is one of them. When Clark fall through the glass, that X-ray "lens" fall in place and thus, enabling Clark to see through things.
If this line of thought is continued, it can also be used to explain the other visions that are available to him in time to come. Some of these visions include telescopic, microscopic and infra-red visions.
Heat Vision
Another related vision is Clark's heat vision. We speculated that this power is actually related to the properties of Gamma-rays. Gamma-rays are often released in molecular fusion and fission as a type of energy. So this vision enables him to concentrate the Gamma-rays in his body at one point and thus, the energy burst forth and starts a fire.
This begs the question, where does it come from? We believe that the Gamma-rays come from the Sun. His body is a large solar battery, capable of storing energy, so we concluded that his body releases the energy he stored from the Sun.
It was mentioned in "Heat" (Season 2, Episode 2) that his hormones played a part. Apparently, it is his hormones that helped him to release the energy stored in his body. Therefore, we concluded that it is his hormones that are actually storing the solar energy, rather his whole body.
Super Hearing
Super hearing, or we would rather call it sensitive hearing, is not a latent effect from Clark's blindness. Martha Kent mentioned in "Whisper" (Season 3, Episode 10) that how Clark's ear "must be trying to compensate for his blindness". Many fans literally took it that it is the latent effect due to Clark's blindness. But we believe that his hearing is firmly a solitude power, not relating to any of his other powers at all.
Clark already got this power quite some time before "Whisper", although it is not explicitly stated. In "Calling" (Season 2, Episode 22), when Clark was at Lex's wedding, he heard a high pitched sound made by the "key". This high pitched sound was later described how it send all the dogs into frenzy and Chloe supplement that unless, Clark has the ears of a dog, he shouldn't hear it at all.
That leads us to believe that Clark's ears is very sensitive and he is able to hear a wide range of frequencies. A normal human being is only able to hear frequencies ranging from 20 Hz to 20 000 Hz, a bat is able to hear higher frequency than human beings, while elephants use very low frequency sounds to communicate. Thus, we believe that Clark's ability to receive frequency exceeds these entire three receivers.
If this is used to explain Clark's sensitive hearing, it should make sense that he is able to pick up only one type of frequency among many other frequencies. Clark learnt, with the help of his parents, how to fine tune this power in "Whisper" (Season 3, Episode 10). In a way, he is like a radio, able to pick up just one frequency among many other frequencies out there.
Flight
The power that made Clark Kent, or rather, Superman famous, flight allows him to fly from one end of the planet to another. We believe that it is actually latent effect of the bio-electric aura (For more information, please refer to the Invulnerability section) surrounding him. We concluded that not only does the bio-electric aura protects him from harm, it also allow him to defy gravity.
This power was first demonstrated briefly in "Metamorphosis" (Season 1, Episode 2), where Clark was floating on top of his bed and later in "Rosetta" (Season 2, Episode 17), where Clark actually floated, rather than fly, from his bedroom to a highway. Clark has mentioned that he told Lex, who found him and drove him, that he sleepwalked, although he "has no idea how much walking is involved". If this is true, then it should not come as a surprise that Kal-El is able to fly in "Crusade" (Season 4, Episode 1).
For the sake of clarity, from here on, we will refer Kal-El as the emotionless and robotic part of Clark, while Clark as the normal self. The reason why Kal-El is able to fly is probably because he has a higher aptitude in controlling the bio-electric aura, which he used it to cancel out the gravitational force acting on him. It was probably due to this manipulation of bio-electric aura that allows him to "push" against the air around him, allowing him to maneuver in the air, hence, giving the impression that he is able to fly around.
Clark, on the other hand, remains earth-bound is probably because of his inexperience at controlling his bio-electric aura. Also, it was mentioned in the show that he has a fear for flying. This could possibly contribute to his inability to fly, because he is subconsciously or unconsciously suppressing his ability to manipulate the bio-electric aura and fly.