What is Change in velocity: Definition and 46 Discussions

Delta-v (more known as "change in velocity"), symbolized as ∆v and pronounced delta-vee, as used in spacecraft flight dynamics, is a measure of the impulse per unit of spacecraft mass that is needed to perform a maneuver such as launching from or landing on a planet or moon, or an in-space orbital maneuver. It is a scalar that has the units of speed. As used in this context, it is not the same as the physical change in velocity of the vehicle.
As a simple example, take a conventional rocket-propelled spacecraft which achieves thrust by burning fuel. The spacecraft's delta-v is the change in velocity that spacecraft can achieve by burning its entire fuel load.
Delta-v is produced by reaction engines, such as rocket engines, and is proportional to the thrust per unit mass and the burn time. It is used to determine the mass of propellant required for the given maneuver through the Tsiolkovsky rocket equation.
For multiple maneuvers, delta-v sums linearly.
For interplanetary missions, delta-v is often plotted on a porkchop plot, which displays the required mission delta-v as a function of launch date.

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  1. S

    Why is the integrated velocity times change in velocity zero?

    So consider a subject system, a galaxy, with stars in it. This galaxy is passed by another object, the perturber. When the interaction is fast, we call this interaction a high-speed encounter. Now we consider that the interaction is really fast. This means that during the interaction, the...
  2. SamRoss

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  3. P

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  4. M

    Finding the change in velocity from an acceleration vs time graph

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  5. K

    Can instantaneous velocity be different from average velocity?

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  6. Sorcerer

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  7. Strange design

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  8. R

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  9. LoganNagol

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  10. Giu1iano

    Change in velocity due to force acting over given time

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  11. x2017

    Change in Velocity after a Collision

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  12. B

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  13. L

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  14. M

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  15. S

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  16. Sneakatone

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  17. R

    How to find Change in velocity on an Acceleration vs TIme Graph?

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  18. N

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  19. J

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  20. N

    How Do You Calculate the Change in Velocity of a Tennis Ball?

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  21. F

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  22. M

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  23. B

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  24. P

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  25. P

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  26. B

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  27. D

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  28. U

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  29. W

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  30. S

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  31. G

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  32. M

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  33. K

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  34. D

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  35. L

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  36. P

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  37. D

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  38. S

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  39. Y

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  40. E

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  41. H

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  42. K

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  43. C

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  44. M

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  45. R

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  46. N

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