The transference of potential energy to kenetic energy and it's effect on momentum

In summary, the conversation discusses an ultra modern spacecraft that is equipped with a potential energy storage system. The ship is accelerated to 50% of the speed of light and gains momentum x, and then the potential energy is converted to kinetic energy, causing the ship's mass to increase by 20%. However, there are misconceptions about special relativity and the relationship between energy and mass.
  • #1
carl fischbach
Lets say that you take an ultra modern spacecraft
like Nasa is researching or may already have and
equip it with a vast potential energy storage
system.Before you embark on your flight a large
quantity of potential energy is stored on board
the ship.The craft is now accelerated to 50% of c
in a straight line.Now we can agree that the craft
possesses momentum x.The ship is traveling at 50%
c and the vast quantity of potential energy,stored
before the fight,is converted to very high speed
particles stored in a ring on board the ship.
Let's say the ships mass has increased by 20%,due
to the conversion of potential energy to kenetic
energy.The ship now possesses momentum y.If you
decelerate the ship in straight line you now have
an imbalanced force*time relationship between
acceleration and deceleration.
There are several possible explanations, the ship
slows when potential energy is converted to
kenetic energy,stored potential energy acts like
mass,the ship does not act heavier when gaining
kenetic energy, or something I've overlooked here.
 
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  • #2


Wow, there really are a lot of misconceptions about special relativity packed into this paragraph. Let's see if we can begin to sort them out.
Originally posted by carl fischbach
and
equip it with a vast potential energy storage
system.
You mean -- fuel?
The craft is now accelerated to 50% of c
in a straight line.
0.5c relative to the stationary earth, I imagine.
Now we can agree that the craft
possesses momentum x.
Momentum depends on the observer. If "we" means specifically "observers on the earth," then sure, we'll call it x.
The ship is traveling at 50%
c and the vast quantity of potential energy,stored
before the fight,is converted to very high speed
particles stored in a ring on board the ship.
Er, okay.
Lets say the ships mass has increased by 20%,due
to the conversion of potential energy to kenetic
energy.
Why should we say this? Where did this 20% figure come from? What sort of potential energy are we talking about?

- Warren
 
  • #3
My understanding was that energy is proportional to mass regardless of the form of the energy - stretch a rubber band (for example) and it gains mass.
 

1. What is the difference between potential energy and kinetic energy?

Potential energy is the stored energy an object has due to its position or composition, while kinetic energy is the energy an object possesses due to its motion.

2. How does potential energy transfer to kinetic energy?

When an object with potential energy is released, it begins to move and the potential energy is converted into kinetic energy. This happens because of the force of gravity or other external forces acting on the object.

3. What is the relationship between kinetic energy and momentum?

Kinetic energy and momentum are both measures of an object's motion. The relationship between the two is that an object's momentum is directly proportional to its kinetic energy. This means that as an object's kinetic energy increases, its momentum also increases.

4. How does the transfer of potential energy to kinetic energy affect an object's momentum?

As potential energy is converted into kinetic energy, the object's momentum increases. This is because the object's speed and mass are both factors in determining its momentum, and as the object accelerates due to the conversion of energy, its speed and thus its momentum also increase.

5. Can kinetic energy and momentum be transferred between objects?

Yes, kinetic energy and momentum can be transferred between objects through collisions or other interactions. In a collision, the total momentum of the objects involved will remain the same, but the distribution of momentum may change. The objects' kinetic energies may also change depending on factors such as mass and speed.

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