Collision course

Does anyone have any idea what happens, if, for example, M1A1 and T-90 collide with speed of say 60 km/h?

 

A lot of noise and angry repair crews. :lol:

 

and a big mess and a probal explosion

 

It says "Phiiiiw" and they both richoche of each other, with a great number of sparks flying all over !! :lol: :lol:

 

it do not matter the results, what is important the bill from the body shop :lol:

 

There is no differece if two objects hit each other at a given speed (e.g. both travelling at 60 km./h.) and one object standing still, with the other hitting it with 60 km./h., from the point of view of the moving object, so you might as well ask what would happen if the tank runs int a parked tank of the same type. We can calculate the damage compared to an incoming shell. We know that we have a 68.7 t. or 68,700 kg. object travelling at 60 km./h. or 16.667 m./s. This gives us a kinetic energy of ((68,700 * 16.667^2) / 2) = 159,027,777.778 Joule. Compare this to the 8,8 cm Pzgr. 39/43, which generates ((10.2 * 1,000^2) / 2) = 5,100,000 Joule. Thus, the kinetic energy is approximately 30 times that of an incoming 8,8 cm Pzgr. 39/43.

Quite a massive impact

 

You can double that if they are coming at each other with 60km/h ! Its that simple

Two tanks driving towards each other at 60km/h, are going to collide with an impact velocity of 120km/h :!!!:

 

like if we are going to see in the middle of combat, play chicken :lol:

 

As mentioned initially, that is not true. Two objects both travelling at speed X colliding will not cause the same damage as one object travelling at speed 2X and colliding with a solid object. You couldn't simply double the factor if the speed was twice as high anyway.

As an example, let's imagine a car weighing 1,000 kg. travelling at 50 km./h. (or 13.889 m./s.), collides with a solid wall. The kinetic energy would be ((1,000 * 13.889^2) / 2) = 96,450 J.. Now, if the car in stead collides with another car of the same weight and travelling at the same speed, and we follow your suggestion that it would mean the equivilance of a 100 km./h. collission, the kinetic energy should be ((1,000 * 27.778^2) / 2) = 385,899 J. - or four times the kinetic energy. Thus, a head-on collision would have to be four times as powerful as driving into a wall, which is clearly not the case.

 

Christian lets forget the wall ! (Despite a wall cant move ! )

Ok one car stands still, while the other come crashing into it with 50km/h. (Both weigh 1000kg) They collide with a force of 96,450 J. The difference of driving into a solid wall and into a non-moving car, is that the car will move under the force of the impact, thus absorbing some of the kinetic energy. While a wall if its solid enough would just take the whole deal, thus maximising the force of impact.

Next test, both cars come crashing towards each other with 50km/h. Each car holds 94,450 j of kinetic energy, now what happens when you put two and two together ?

The only difference now is that both cars are in motion, and won't move under the force of the impact. In effect they will both react like a solid wall.

KBO

 

For example a 1000kg car coming at 10m/s will have a Kinetic energy of 50,000 j. A car with the same weight coming at 20m/s will have kinetic energy of four times that ! =20,000 j !.

KBO

 

You don't understand the argument.

It is true that the physical characteristics between a car and a wall will change the outcome, but there will not be any difference in the outcome between a car standing still, and which does not move, while the other car drives into it, and two cars colliding.

This still does not change the fact, that the velocity of object A will not change the kinetic energy generated by object B.

Furthermore, you disprove yourself, in that your adding up the kinetic energy generated by the impact only gives half the kinetic energy of the impact you suggested. Furthermore, the amoount of kinetic energy you get when you add the kinetic energy of the two cars will not effect both cars - otherwise, the total amount of kinetic energy would suddenly have doubled, which is physically impossible. Rather, the double amount of kinetic energy will be shared by the two cars, and therefore the original amount will be left.

 

This probably explains why tanks were given guns instead of bull-bars. It does suggest the amusing possibility of tanks with crumple zones and airbags

 

Shall I split this topic or just leave it here as an example to all who wish to challenge Christian on physics? :lol:

 

No i didnt disprove myself ! You just thought i meant the double amount of Kinetic energy, while what a mean was the speed of the collision would be 120km/h not still 60km/h.

Do we agree that two cars coming at each other with 60km/h, are going to collide with 120km/h ? (Because thats what is going to happen !)


Fact is a car weighing 1000kg, colliding with a non-moving car of same weight at 60km/h, will do less damage than if it was a solid wall wich was rammed ! (A wall won't absorb any energy, it will just take the whole deal !)

 

It doesn't make any sense to make an argument that way. It is true that 60 + 60 = 120 (though, strictly speaking, 60 km./h. + 60 km./h. isn't exactly 120 km./h., because velocities can't be added like that, but the difference is too small to notice). This does not mean, however, that each car will suffer as if it colided with 120 km./h., so we can't use that information for anything. The collision itself doesn't move, it is an event. We do not agree that they will collide with the same force as one object travelling at 120 km./h. crashing into a non-moving object. The damage to each car will be that of a car crashing into another car at 60 km./h. where the car it crashes into doesn't move. It will not give each car the damage of a car crashing into another car that doesn't move at 120 km./h. That is not what is going to happen!

Your final point just shows that you either don't understand anything, or is trying to provoke. Obviously, a wall will not react the same war as a car. Furthermore, the wall will be just as likely to move as a car, if it has the same weight (law of inertia).

To put it differently, I will set up a scenario you may be able to understand. Let me know if I loose you!

We have two objects. For the sake of understanding, I will assing them identities:

• A (car)
• B (wall)

Both objects are moving:

• A (car) is travelling east at 60 km./h.
• B (wall) is travelling west at 60 km./h.

Object A (car) and B (wall) are on a direct collision course.

When A (car) hits B (wall), A (car) will be damaged by force X.

Now, same scenario, however this time the velocity of B (wall) is 0 km./h.

When A (car) hits B (wall), A (car) will still be damaged by force X.

Clear?

Now, if we bring other factors into play, there will be more variables, and this will change the outcome, however the implied statement above is true - that the speed object A hits object B with is the only velocity variable we need. The speed on object B doesn't influence the damage of object A. If the opposite was true, it would mean that force would occur from nothing, which is not possible.

Since the only variables we have above is velocity (and, by research, mass) of the two tanks in the original question, the speed of the second tank will not influence the damage to the first tank. If we have the molocylar structure of the entire tank, and the surrounding area (air, ground, etc.), we could include these factors into the calculation to find the initia, but this calculation would be complex, and woudl matter little in the final conclusion.

 

No it shows you are very easely provoked, and will provoke back !! Because i made no intension to provoke you !

60km/h + 60km/h is 120km/h, the difference is so minimal you wouldnt be able to see it !

My point is: A car that runs into a non-moving car at 60km/h, isnt going to do the same damage as if they both come towards each other at 60km/h.

Ok lets put it like you said:

Scenario 'A':

Both cars weigh 1000kg.

Car(A) is coming at lets say 10m/s towards car(B) wich is standing still.

Now car(B) is motionless meaning it has no kinetic energy stored with it !. Car(A) is in motion (10m/s) and stores 50 kj of Kinetic energy.

So the force of the impact can only be 50 kj, no more as only one car carries Kinetic energy.

Scenario 'B':

Both cars weigh 1000kg.

Car(A) and Car(B) are both coming at each other at 10m/s.

Both cars are now in motion, and now 'both' hold 50 kj of kinetic energy.

Now the force of the impact has to be 100 kj and not still 50 kj, because the energy of either car won't just disappear ! (That is impossible!)
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Now Christian lets keep this peacfully, im not going to argue with you !!


Regards, KBO.

 

wow, that a lot of energy in the tank,but consider that in any shell all that energy is focused in a small area plus the speed it is traveling and you have the terrible effect of armor piercing

 

Yes, but before the energy only affected car A, now it affects car A and B, thus 50 Kj. for each car.

It's true that the area is smaller, but this only means that the pressure on a specific point is higher (which is why it can penetrate the armour). The speed in calculated into the force already.

 

Yes for each car ! And when they are put together to resemple the force of impact, it gives 100 kj !

I mean, 50 kj of energy can't just disappear !.

Best regards, KBO.