So a rocket moves by having a big explosion push it. A car moves by little tiny explosions moving things and then mechanics to get it to the wheels, how does light power itself to move? especially with how fast it moves?
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Move is a vague term. It could mean either acceleration or velocity, or both. Acceleration is something changing its velocity, either the speed itself or the direction.
A car accelerates with tiny explosions. It decelerates with friction of the road, air resistance, or brakes. Rockets accelerate or decelerates with big explosions. When none of those things apply, like a rocket or car in space, it is still moving with its velocity, it’s just not accelerating or decelerating.
Light doesn’t change its velocity, it can only change direction. It has “infinite” velocity. From the moment it comes into existence to the moment it disappears, a photon is moving at the same speed, “infinite”. There’s a bit of misnomer when we say the speed of light is about 300,000 km/s. That speed is the fastest anything can move in the universe, not just light. Even the effects of gravity moves at this speed. It’s why it’s referred to as the speed of causality. If the sun simply vanishes with all its mass, it will take approximately 8 minutes for the earth to stop orbiting where the sun used to be. Light when you think of it a certain way has “infinite” speed, but the speed of light is finite because it is being restricted by the universal speed limit. If scientists increase the speed of causality, light will move faster to match it (kudos if you get the reference).
Light is a self-propagating change in the electric and magnetic field. When the electric field changes, it causes the magnetic field to also change. When the magnetic field changes, it causes the electric field to change. It’s a self-feeding cycle that repeats until something interrupts it, like running into an electron. We use this relationship everyday, it’s what allows us to make electricity using generators and electric motors move. The change happens almost instantaneously, but the universal speed limit prevents it from being truly instant. Light moves because it has energy. Much like how that spaceship or car continues to move through space without those explosions if it has kinetic energy and nothing else runs into it. But because light has no mass, it has “infinite” speed. The only reason that car or spaceship isn’t travelling at the speed of light is because they have mass. If they didn’t have mass… They would be moving at the same speed of light but as far as we can tell the only way to do that is to have it run into its antimatter equivalent and turn itself into pure energy.
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