Does Higher Specific Impulse Mean Greater Distance Traveled in Space Probes?

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Cinitiator
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Imagine there are 2 space-probes in space. Both of them start their engines in the same time. The first space-probe has a very low level of thrust but a very high specific impulse. The second space probe has a very high thrust but a very low specific impulse.
Both of them have an equal amount of fuel.

Is this statement true? (the statement is true in my opinion - just making sure I understand the specific impulse concept):
If the fuel is consumed on the first space probe, it means that it traveled a longer distance than the second space probe, no matter what time has passed after the consumption of the fuel.
 
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Hi Cinitiator! :smile:
Cinitiator said:
Is this statement true? (the statement is true in my opinion - just making sure I understand the specific impulse concept):
If the fuel is consumed on the first space probe, it means that it traveled a longer distance than the second space probe, no matter what time has passed after the consumption of the fuel.

Yes.

Specific impulse = momentum per mass of fuel: so more momentum = more distance! :smile:

From the PF Library …
Specific impulse:

Specific impulse is impulse per mass of propellant (fuel).

It equals change in momentum per mass of propellant, and so measures the efficiency of rocket and jet engines.

See http://en.wikipedia.org/wiki/Specific_impulse.

(This is rocket science! :wink:)​