speed of light?

Question

If light (travelling at velocity v1=C) is bent upon entering a prism by being slowed down to v2

Answer 1

The speed of light is constant. The index of refraction appears to impact the speed of light. When entering the prism, the speed is a function of the angle theta (the light is bent). You can resolve the speed into two vectors.

Vy = CsinTheta; the velocity in the Y direction.
Vx = CcosTheta; the velocity in the X direction.

Therefore, the total speed is equal to the root of Vy^2+Vx^2.

In air (the light is not being bent usually) = C. So, the formula equals Vx=CcosTheta; where theta equals 0 degrees. Therefore,
you get the maxium horizontal speed.

Because of this, it is only a one directional vector. You are not impeding the velocity by the angle of refraction.

Also, Be WARY of FOLK using Kinetic Energy and Potential Energy. This is not a conservation of energy problem. This is a simple problem that focuses on breaking light into two vectors (speed in the X and Y)

Answer 2

Light is actually interacting with matter in the prism, but you can look at it in this way: When you toss a ball up in the air, as it slows down towards the top, its kinetic energy is converted into potential energy, which is restored to the ball when it comes down. Likewise, as the light slows inside the prism (yes, it actually does slow down), the "kinetic energy" of the light is converted to another form of energy acting as its potential energy, and that's the INCREASED frequency of light. There is no change in total energy of the light as it enters or leaves the prism. But in fact, because this is a light-matter interaction, it's more accurate to say that energy flux remains a constant.

Answer 3

Not really. Force and velocity is reduced by friction and there is none but there is the idea that light is made up of particles and they may be some bumping against other particles and this may result in its slightly reduced velocity. But its escape velocity actually returns to normal once out.

Answer 4

at first, the size of the cost is the observer who sees the cost of the spacecraft being only decrease than the cost of sunshine (i.e., on the launch internet site), no person on that spacecraft. He additionally sees the spacecraft modern-day technique fairly extreme mass, length and time dilation. So, while he sees the intrepid astronaut hop on his motorbike, he sees that for the period of very sluggish action, and the cost he sees, one hundred eighty mph or so which you would be able to the astronaut, is only a tiny fraction of the 10mph required to interrupt the SoL. So, no, the observer sees only a motorcyclist making a bare enhance over the spacecraft itself. Worse, this is going to become an excellent smaller fraction the speedier the spacecraft is going, and the speedier the motorbike is going, it procedures the cost of sunshine by skill of an incrementally declining share of the relax speed required.

Answer 5

from the laws of conservation of energy, the total kinetic energy, K.E., must be equal to the potential energy,P.E., i.e., K.E.=P.E.. hence K.E.-P.E.=0. When a light beam enters the prism, we know that its velocity decreases. this decrease in velocity resuts in a decrease in kinetic energy, but increase in potential energy of the wave. when the wave has exited the prism, there is less surface that restricts the motion of the light, thus its regains its velocity,c, when the potential energy is reconverted to kinetic energy.

Answer 6

But I think light has no mass, at least according to classical mechanics. So no force should be needed to accelerate it.

Answer 7

It would seem like that but the soldiers analogy doesn't hold water. Try sailors.

Answer 8

I agree with you, the additional force thing!

Answer 9

Oh yes I'm sure your right

Answer 10

dude... speed of light? simple! 299,999,997km/s
and i am not kidding. seriously!