What is the formula for calculating delta v for escape velocity?

AI Thread Summary
To calculate the delta v required for an object to achieve escape velocity and have a velocity of 1 km/s at infinity, the formula used is vescape = circular velocity * sqrt{2}. The additional velocity needed is 1 km/s, which must be added to the escape velocity to determine the total delta v required. The correct formula for the required velocity is vrequired = sqrt{vescape^2 + vinfinity^2}. The discussion also touches on formatting mathematical expressions using TEX, with participants sharing insights on how to properly use the square root function. Overall, the conversation highlights the calculations involved in transitioning from a circular to a hyperbolic orbit.
tony873004
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Let's say I have an object orbiting the Sun in a circular orbit with an orbital velocity of 30 km/s. If I want to accelerate prograde into a hyperbolic orbit, and I'd like my velocity relative to the Sun to be 1 km/s at infinity, what is the formula I'd use to figure out how much delta v in the prograde direction I'd have to apply? I believe the formula for escape velocity is circular velocity * sqrt{2}, but I want to know how much further I must accelerate to have 1 km/s of extra velocity when the rocket has distanced itself from the Sun.

Also, how do I get the root symbol in the tex tags?
 
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You would have to accelerate 1 km/sec more.

The root function for squareroot is \sqrt{n} the radical sign will be placed over n like this:
\sqrt{2}

or
\sqrt{\frac{2GM}{R}}
 
Never mind... I figured it out. :wink:
vescape = \sqrt{2}*vcircular
vrequired = \sqrt{vescape^2 + vinfinity^2}

edit... to change to TEX format. I love these TEX things. Thanks Janus.
 
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Janus said:
You would have to accelerate 1 km/sec more.
I must have been typing while you were posting.
That was my original guess, but it didn't work. The formula in the above post works though. Thanks, Janus.

BTW... Is your name in reference to Saturn's moon? That's a cool moon as it shares a horseshoe orbit with Epimetheus.
 
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