The top speed isn't quite limited to the velocity of the exhaust
No no no. Top speed is not limited to the exhaust velocity in any way.
most propulsion systems tend to have a constant force they can apply to ever decreasing mass
exactly... so answer me this:
You have a spacecraft that has a mass of 100kg, of which 90kg is reaction mass. Its engine can produce a force of 100 newtons and consumes 0.1kg of reaction mass per second. If the spacecraft begins at rest and fires its engine until all reaction mass is used, what is its final velocity?
You can find an answer to that question with no additional information... notice how exhaust velocity is nowhere to be found?
So your top "speed" is limited to exhaust velocity.
No, you get an F in high school physics.
Lets take a very simple example... Lets say you have a spacecraft that is mostly reaction mass. Within your own frame of reference you are at rest. Now you push 50% of your spacecraft away at 10mph. This gives your craft a velocity of 5mph and the portion that you pushed away 5mph in the opposite direction (relative to your original frame of reference). Now you push away 50% of what is left, again at 10mph. This gives your ship a 5mph boost. Repeat one more time and your space ship has a velocity of 15mph.
Clearly, top speed is NOT limited to exhaust velocity.
We should be making it harder for politicians to hide this sort of thing. If we could look at bank statements of every politician, we could see that congressman X didn't pay a dime when their garage was put in, or apparently went on vacation for free. If these things were easily traceable, politicians might think twice about accepting these types of gifts.
From the personal side - Which would you rather do, spend 5 minutes on an elevator and a couple minutes walking to get to work, or drive 20 minutes(possibly in heavy traffic), still have to walk several minutes to get from your car to work. Maintaining a car is probably $400/month, minimum, a bus pass in some areas is $100 or more(unsubsidized), even subway tokens cost money. Or you can ride a free elevator*. It could easily free up an hour/day for other pursuits.
*Well, the cost of the elevator is in the rent/association dues, but would be there anyways for multilevel dwellings.
None of the above. Living in large cities sucks IMHO. I'd rather live on the edge of a smallish town or in the country entirely, running my own business on my own property. Little noise and traffic, no crowds to speak of, clean air and trees to look at out your window instead of concrete. I'd be willing to pay a lot more in order to live like that and avoid city life.
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The top speed isn't quite limited to the velocity of the exhaust
No no no. Top speed is not limited to the exhaust velocity in any way.
most propulsion systems tend to have a constant force they can apply to ever decreasing mass
exactly... so answer me this:
You have a spacecraft that has a mass of 100kg, of which 90kg is reaction mass. Its engine can produce a force of 100 newtons and consumes 0.1kg of reaction mass per second. If the spacecraft begins at rest and fires its engine until all reaction mass is used, what is its final velocity?
You can find an answer to that question with no additional information... notice how exhaust velocity is nowhere to be found?
So your top "speed" is limited to exhaust velocity.
No, you get an F in high school physics.
Lets take a very simple example... Lets say you have a spacecraft that is mostly reaction mass. Within your own frame of reference you are at rest. Now you push 50% of your spacecraft away at 10mph. This gives your craft a velocity of 5mph and the portion that you pushed away 5mph in the opposite direction (relative to your original frame of reference). Now you push away 50% of what is left, again at 10mph. This gives your ship a 5mph boost. Repeat one more time and your space ship has a velocity of 15mph.
Clearly, top speed is NOT limited to exhaust velocity.
We should be making it harder for politicians to hide this sort of thing. If we could look at bank statements of every politician, we could see that congressman X didn't pay a dime when their garage was put in, or apparently went on vacation for free. If these things were easily traceable, politicians might think twice about accepting these types of gifts.
From the personal side - Which would you rather do, spend 5 minutes on an elevator and a couple minutes walking to get to work, or drive 20 minutes(possibly in heavy traffic), still have to walk several minutes to get from your car to work. Maintaining a car is probably $400/month, minimum, a bus pass in some areas is $100 or more(unsubsidized), even subway tokens cost money. Or you can ride a free elevator*. It could easily free up an hour/day for other pursuits.
*Well, the cost of the elevator is in the rent/association dues, but would be there anyways for multilevel dwellings.
None of the above. Living in large cities sucks IMHO. I'd rather live on the edge of a smallish town or in the country entirely, running my own business on my own property. Little noise and traffic, no crowds to speak of, clean air and trees to look at out your window instead of concrete. I'd be willing to pay a lot more in order to live like that and avoid city life.