Endercreeper01

how then?

Then it would just be that it blocked 1/2 of the light before, if everyone agreed because to an outside observer, the paper shrinks and to the paper, the light source shrinks by 1/2

Well, relative to an outside observer, then I guess they would see that (if the could read your thoughts)

I want to know the part about how you calculate how strong a force is between 2 magnets and the magnetic field, B.

No, special relativity is called relative for a reason. In special relativity, then space and time are relative and not absolute, so then not everyone has to agree on the pecentage

so then it does not depend on speed.

it is time dependent, but it is not a huge effect for this. it is time dependent, but it is not a huge effect for this.

it is time dependent, but it is not a huge effect for this.

it is time dependent, but it is not a huge effect for this.

it is time dependent, but it is not a huge effect for this.

it is time dependent, but it is not a huge effect for this.

There is a dependance on speed, but it is too small to consider

Yes, but as studiot said, why should it depend on velocity?

According to the wiki article, it does not depend on speed

I meant an object such as a sphere rolling along a surface. It does not seem to depend on velocity, according to the Wikipedia article.

Yes, but does rolling resistance depend on speed?

When you have a object rolling across a surface, then it is not friction slowing it down, It is air resistance. Here is why. When you have an object rolling across a surface, then the force of friction is μN, where μ is the kinetic friction coefficient and N is the normal force. In this case, it is on earth, so then N=mg and so F=mgμ. When you put a force on an object greater then that force, then friction does not stop it because friction does not depend on the object's velocity. What really stops it should be the air because air resistance is proportional to v^2, so as it accelerates, air resistance gets bigger and bigger, slowing it's acceleration more and more until a=0 and then it slows it down until it stops, so air is what stops it. Is this correct?

How do you calculate a magnetic field B?

What is the force of magnetism between 2 magnets?

oh oh

Then what is the correct equation? Then what is the correct equation?And it is relativity because it uses special relativity And it is relativity because it uses special relativity

Then what is the correct equation?

why not? With gravity, everything accelerates towards another mass at the same rate, regardless of its mass, so even if it gains more and more mass, then it still accelerates towards it at the same rate (actually it accelerates at a faster rate), and eventually it can get to the speed of light

Is it possible to use gravity to accelerate something to the speed of light? past the swartzchild radius then could something accelerate to c?

you need energy to make a force do work on an object ohAnd I did reply to your posts