Infinite Rocks Collide: Is the Impact Elastic?

In summary, the conversation discusses the possibility of an elastic collision between an infinitely large rock and an infinitesimally small rock, with varying velocities and masses. It is stated that elastic collisions are rare in practice and that using terms like "infinitely" and "infinitesimally" is not acceptable. The analogy of shooting a bullet at a mountain is used to illustrate the idea that the small rock would most likely shatter and pulverize upon impact with the large rock. The concept of Einstein's equation, e=mc2, is also mentioned in relation to the potential impact of a bullet on a mountain.
  • #1
CandleSnuff
1
0
If an infinitely large rock is traveling infinitesimally slow along a straight line and an infinitesimally small rock is traveling infinitely fast towards the infinitely large rock along the same axis, is the collision elastic?
 
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  • #2
In practice elastic collisions are almost impossible. As far as I know only molecules in the kinetic theory are treated with elastic collisions.

And terms as "infinitely fast" for matter is not acceptable.
If you change your words to 'really big', 'really small', 'really slow', and 'really fast', I would say the small rock would just shatter and pulverize.
 
  • #3
The problem you're setting is just like shooting a bullet in a mountain. What do you think would happen?
 
  • #4
Dr Lots-o'watts said:
The problem you're setting is just like shooting a bullet in a mountain. What do you think would happen?

I think that is why he is specifying the high/low mass and high/low velocity. According to e=mc2 a bullet would have no effect on a mountain. But a bullet traveling at .9999c would have a very noticeable effect on a mountain.

EDIT: Not that a bullet wouldn't have still a very noticeable effect on a mountain at speeds of lower than .9999c.
 
  • #5


Based on the given scenario, it is difficult to determine whether the collision between the infinitely large and infinitesimally small rocks would be elastic. In order to determine the elasticity of a collision, we need to consider the conservation of energy and momentum.

In this case, since the infinitely large rock is moving at an infinitesimally slow speed, its momentum would be close to zero. On the other hand, the infinitesimally small rock is moving at an infinitely fast speed, which would result in a very high momentum. When the two rocks collide, their momenta would be equal and opposite, leading to a significant change in momentum.

However, since the speeds and masses of the rocks are approaching infinity and zero respectively, it is possible that the change in momentum would be negligible and the collision could be considered elastic. This means that the total kinetic energy before and after the collision would be the same.

Furthermore, the elasticity of the collision would also depend on the properties of the rocks, such as their elasticity and hardness. If the rocks are highly elastic and can withstand the impact without deforming, then the collision could be considered elastic.

In conclusion, without knowing the specific properties and conditions of the rocks in question, it is difficult to determine whether the collision would be elastic. However, based on the given scenario, it is possible that the collision could be considered elastic due to the high speeds and small masses involved. Further experimentation and analysis would be needed to accurately determine the elasticity of such a collision.
 

1. How does the impact of infinite rocks affect their elasticity?

The impact of infinite rocks can cause a change in their elasticity. As the rocks collide, they transfer energy and create stress within each other, potentially altering their ability to return to their original shape after deformation.

2. Can the impact of infinite rocks be considered elastic?

It depends on the type of impact and the properties of the rocks involved. In some cases, the impact may be elastic, meaning that the rocks will return to their original shape after the collision. In other cases, the impact may be inelastic, meaning that the rocks will permanently deform and not return to their original shape.

3. How do scientists measure the elasticity of rocks?

Scientists measure the elasticity of rocks by conducting experiments, such as compressing or stretching the rocks and recording the amount of force needed to cause a certain amount of deformation. They can also use specialized equipment, such as a stress-strain analyzer, to measure the response of rocks to different levels of stress.

4. What factors can affect the elasticity of rocks during an impact?

The elasticity of rocks during an impact can be affected by various factors, such as the speed and angle of impact, the composition and structure of the rocks, and the temperature and pressure at the time of impact. These factors can influence the amount of energy transferred and the resulting stress and deformation within the rocks.

5. How does the elasticity of rocks impact their ability to withstand an impact?

The elasticity of rocks can play a crucial role in their ability to withstand an impact. Rocks with high elasticity will be able to absorb more energy and deform without breaking, allowing them to better withstand the impact. On the other hand, rocks with low elasticity may shatter or fracture under the same amount of force, making them less able to withstand the impact.

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