# Can you go fast enough to get enough mass to become a black hole?

To start with, your mass is not affected at all by the speed that you travel at. People tend to believe that objects gain mass as they travel at higher speeds, mainly because old textbooks and teachings have us believe that.

But according to Einstein’s theory of Special Relativity, this is simply not true.

## So why were we taught that objects gain mass when travelling at high speeds?

The main reason that we have been taught this for so long could be because there is something called ‘relativistic mass’ which is not the same as regular mass. Without going into too much detail, when it comes to relativistic mass, the statement of gaining mass when you gain speed could actually be true.

This is the reason we have been taught it about regular mass. This means that the teaching of this statement is very misleading when they are about two completely different things.

It is misleading today to treat the motion energy of something as relativistic mass, but that is why some people believe it to be true. ## So, what does an object gain if it does not gain mass?

When an object is gaining speed whilst travelling, it does not gain mass, but it does gain kinetic energy. This means that the total energy of any moving object is its rest energy plus its kinetic energy. Interestingly, the rest energy of something is in its mass.

## What is relativistic energy?

The equation for relativistic energy is as follows:

E = mc2/(1-v2/c2)1/2

In which E is the relativistic energy, m is the mass (this does not change remember! Even if the speed of the object changes), c is the speed of light (which is 299,792,458 m/s), v is the speed of the object. When an object is not moving at all, so v=0, you will just be left with E = mc2.

This is just the equation for mass-energy equivalence. This means that the rest energy of an object would then equal mc2, which simply shows that the rest energy of an object is contained fully in the mass.

## What does that leave?

So, that leaves:

EK = mc2(1/(1-v2/c2)1/2 – 1)

And this equation just shows that, as the speed increases, so does the kinetic energy. EK is therefore total energy minus the reset energy of an object. The equation also shows that the mass never changes.

A very interesting fact is that when an object’s speed reaches close to the speed of light when in a vacuum, the object will have infinite kinetic energy.

Objects with a mass, however, cannot travel at the speed of light exactly when in a vacuum, since that would require an infinite input of energy which is not possible. But objects with mass can still get very close to the speed of light.

Mass is a property of an object. It can describe two things:

• It can describe the object’s resistance to acceleration. Because of this, objects with a greater mass will accelerate less when a force is applied.
• It can also describe the object’s ability to experience gravity or feel the effects of the force. Again, larger masses will experience larger forces from a gravitational field.

So, when an object is travelling at a very high speed, its resilience to acceleration will not change, as well as its ability to feel gravity. Therefore, an object’s mass will not change when it travels at a high speed.

This is supported and predicted by Einstein’s theory. This is also a fact that has been experimented on and verified through said experiments.

## But what about turning into a black hole?

As cool as it would be, sadly, an object cannot be turned into a black hole. So, the answer to the original question is that you cannot get to any speed fast enough to turn into a black hole thanks to gaining mass.

This is mainly because an object will not gain mass when it travels hat high speeds. Even if an object was travelling close to the speed of light, it would still not gain mass.