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Mission to Mars!


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#1 wolfgang

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Posted 02 March 2013 - 06:34 PM

Suppose that we have on the moon a space station which is the only source of fuel and on it there are  unlimited number of identical spaceships,  We want to send one of them  to Mars, each spaceship has a fuel capacity to allow it to fly exactly 1/4 way  to Mars (without fuel the spaceship will miss its direction and may explode!).
Each spaceship has the ability to refuel  by a second spaceship through a specific connection between them without loss of speed . What is the fewest number of spaceships necessary to  accomplish this mission  without losing any one of them?

Note:1- Each spaceship must have enough fuel to return safe to the base space station .

         2- The time and fuel consumption of refueling can be ignored. (so we can also assume that one spaceship can refuel more than one spaceship  at the same time).

       


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#2 k-man

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Posted 02 March 2013 - 08:23 PM

The thing about the space travel is that it doesn't require fuel to cover the distance. The fuel is required to break free of the gravity and to establish the direction and speed. Once you're far enough from any large celestial bodies you can cover arbitrarily large distances without any fuel consumption. So the fuel consumption is not proportionate to the distance, but is proportionate to the masses of the celestial bodies you're launching from or you're in gravitational field of.

 

Anyway, assuming that the fuel is consumed at a constant rate for the distance travelled I have a couple of questions:

 

1) Does the spaceship that reaches Mars also have to return to the station?

2) Can the spaceships that return to the base be used again, and if so, then do we count the number of spaceships used or do we count the number of spaceship launches?


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#3 bushindo

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Posted 02 March 2013 - 11:02 PM

The thing about the space travel is that it doesn't require fuel to cover the distance. The fuel is required to break free of the gravity and to establish the direction and speed. Once you're far enough from any large celestial bodies you can cover arbitrarily large distances without any fuel consumption. So the fuel consumption is not proportionate to the distance, but is proportionate to the masses of the celestial bodies you're launching from or you're in gravitational field of.
 
Anyway, assuming that the fuel is consumed at a constant rate for the distance travelled I have a couple of questions:
 
1) Does the spaceship that reaches Mars also have to return to the station?
2) Can the spaceships that return to the base be used again, and if so, then do we count the number of spaceships used or do we count the number of spaceship launches?

 
 
k-man makes a good point. For the sake of the puzzle, let's assume that the fuel spent is proportional to distance travelled. Let's also assume that the ship that gets to Mars will need to return home.

Spoiler for


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#4 wolfgang

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Posted 03 March 2013 - 11:06 AM

The thing about the space travel is that it doesn't require fuel to cover the distance. The fuel is required to break free of the gravity and to establish the direction and speed. Once you're far enough from any large celestial bodies you can cover arbitrarily large distances without any fuel consumption. So the fuel consumption is not proportionate to the distance, but is proportionate to the masses of the celestial bodies you're launching from or you're in gravitational field of.

 

Anyway, assuming that the fuel is consumed at a constant rate for the distance travelled I have a couple of questions:

 

1) Does the spaceship that reaches Mars also have to return to the station?

2) Can the spaceships that return to the base be used again, and if so, then do we count the number of spaceships used or do we count the number of spaceship launches?

Thanks...I know that the space travel doesn`t  need fuel,but I wanted to be a kind of energy used by the machine to keep it working.

for your 1st question: The spaceship or ships reaching mars should have an amount of energy  keeping  them doing their mission.

2- Yes, the spaceship that returns can be sent again and again, so I need number of ships used.


Edited by wolfgang, 03 March 2013 - 11:06 AM.

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#5 wolfgang

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Posted 03 March 2013 - 11:25 AM

The thing about the space travel is that it doesn't require fuel to cover the distance. The fuel is required to break free of the gravity and to establish the direction and speed. Once you're far enough from any large celestial bodies you can cover arbitrarily large distances without any fuel consumption. So the fuel consumption is not proportionate to the distance, but is proportionate to the masses of the celestial bodies you're launching from or you're in gravitational field of.
 
Anyway, assuming that the fuel is consumed at a constant rate for the distance travelled I have a couple of questions:
 
1) Does the spaceship that reaches Mars also have to return to the station?
2) Can the spaceships that return to the base be used again, and if so, then do we count the number of spaceships used or do we count the number of spaceship launches?

 
 
k-man makes a good point. For the sake of the puzzle, let's assume that the fuel spent is proportional to distance travelled. Let's also assume that the ship that gets to Mars will need to return home.

Spoiler for

I want the fewest number of ships required , and at least one of them should launch with enough energy keeping it working.


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#6 bushindo

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Posted 03 March 2013 - 08:52 PM



I want the fewest number of ships required , and at least one of them should launch with enough energy keeping it working.

 

If you want the number of unique ships required, then

Spoiler for


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#7 wolfgang

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Posted 05 March 2013 - 08:28 PM

Well...9 ships are too much...try to reduce the number


 

I want the fewest number of ships required , and at least one of them should launch with enough energy keeping it working.

 

If you want the number of unique ships required, then

Spoiler for


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#8 BobbyGo

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Posted 05 March 2013 - 11:26 PM

Can one ship transfer fuel to multiple ships simultaneously?  Can one ship receive fuel from multiple ships simultaneously?


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#9 bushindo

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Posted 06 March 2013 - 05:54 PM

Well...9 ships are too much...try to reduce the number

 

I don't think the number of ships can be reduced below 9. Here is why

Spoiler for


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#10 wolfgang

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Posted 07 March 2013 - 02:03 PM

Dear Bushindo....you should notice that I have concidered the moon as our base station(!) and not the earth.So you should  think a little bit (laterally),and try to reduce the number to 5 ships only!...note : all of them will reach mars

Well...9 ships are too much...try to reduce the number

 

I don't think the number of ships can be reduced below 9. Here is why

Spoiler for


Edited by wolfgang, 07 March 2013 - 02:03 PM.

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