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Slingshot effect (1 Viewer)
- Thread starter undalay
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SpinCobra
Member
Dunno bout momentum being transferred but yes, kinetic energy can be lost to a planet.
Planets rotate on their axis, and aside from that rotate around the sun. If you approach the planet from behind their rotational direction, you gain kinetic energy and speed up. As you leave the planets gravitational field, you slow down, but you have excess as you used the planets motion around the sun.
If you approach from the front of a planets path around the sun, its reversed and you slow down.
Dont think that was a clear explanation.. And dont think i answered your question either.
Planets rotate on their axis, and aside from that rotate around the sun. If you approach the planet from behind their rotational direction, you gain kinetic energy and speed up. As you leave the planets gravitational field, you slow down, but you have excess as you used the planets motion around the sun.
If you approach from the front of a planets path around the sun, its reversed and you slow down.
Dont think that was a clear explanation.. And dont think i answered your question either.
No you didn't lol 
Firstly for the slignshot effect. Maximum kinetic energy gain, is when the probe meets the planet head on, the probe will speed up the most this way (source: surfing physics), so that kinda contradicts how you said it will slow down (what are your sources?).
My questions still stand:
Can momentum be transfered from space probe to a planet?
If so, what are the conditions for this.
If not, why ?
Firstly for the slignshot effect. Maximum kinetic energy gain, is when the probe meets the planet head on, the probe will speed up the most this way (source: surfing physics), so that kinda contradicts how you said it will slow down (what are your sources?).
My questions still stand:
Can momentum be transfered from space probe to a planet?
If so, what are the conditions for this.
If not, why ?
SpinCobra
Member
Jacaranda HSC Physics.
The forward momentum of the planet and gravity acts on the spacecraft and speeds it up. In the first picture.
The second picture, the momentum of the planet is in the opposite direction to the spacecraft. As it enters its gravitational field it speeds up, but as it escapes it gravitational field, the craft actually slows down.
If as in momentum you mean energy being conserved than yes. The slingshot effect basically a perfectly inelastic collision, where the bodies do not touch in any way, which means there arent any energy losses.
Edit: Ohh. You said swing into it head on. If you mean swing into it head on into its orbital path, and leaving the same way you came? Then yeah, it speeds up.
Err..
The forward momentum of the planet and gravity acts on the spacecraft and speeds it up. In the first picture.
The second picture, the momentum of the planet is in the opposite direction to the spacecraft. As it enters its gravitational field it speeds up, but as it escapes it gravitational field, the craft actually slows down.
If as in momentum you mean energy being conserved than yes. The slingshot effect basically a perfectly inelastic collision, where the bodies do not touch in any way, which means there arent any energy losses.
Edit: Ohh. You said swing into it head on. If you mean swing into it head on into its orbital path, and leaving the same way you came? Then yeah, it speeds up.
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think about it logically maybe.
If a very big thing and a very small thing collide into each other and its perfectlly inellastic. Then there will be a transfer of momentum but since the very big thing has greater momentum than the small thing the transfer of momentum is negilable. Since the momentum lost by the small will jst be gained again from the big thing.
lolz, ive got noidea if that works but it seems to make sense to me
If a very big thing and a very small thing collide into each other and its perfectlly inellastic. Then there will be a transfer of momentum but since the very big thing has greater momentum than the small thing the transfer of momentum is negilable. Since the momentum lost by the small will jst be gained again from the big thing.
lolz, ive got noidea if that works but it seems to make sense to me
uberturtle
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nah albert stop making things up
kooltrainer
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nah the surfing book is wrong.. it will speed up when u approach from the back.. momentum is transferredundalay said:No you didn't lol
Firstly for the slignshot effect. Maximum kinetic energy gain, is when the probe meets the planet head on, the probe will speed up the most this way (source: surfing physics), so that kinda contradicts how you said it will slow down (what are your sources?).
My questions still stand:
Can momentum be transfered from space probe to a planet?
If so, what are the conditions for this.
If not, why ?
Shadem
New Member
to answer the question
yes
there is momentum transfered from the probe to the planet
the thing is though
that the energy lost so small when you think about the size and relative mass of the planet when compared to the probe
that the change in energy is barely visible
yes
there is momentum transfered from the probe to the planet
the thing is though
that the energy lost so small when you think about the size and relative mass of the planet when compared to the probe
that the change in energy is barely visible
ONe simple answer: YES. Almost everyone (teachers, textbooks) says sling shot is a process whereby a space probe **gains** energy and momentum from a *moving* planet. But there is another version of slingshot when purposely the space probe has to be slowed down, and thereby losing energy to a moving planet. This is requied for missions to **inner** planets like Mercury and Venus. It is because as a spaceprobe moves closer and closer to the Sun, it gains KE from the loss in GPE. The best example is the current mission to Mercury, called Messenger. Another example is **after** the Cassini spaceprobe had entered into the orbit of Saturn, it used the moons of Saturn to slow it down further.
The sources are from NASA, and so valid and reliable (and primary source too!)
Teacher
The sources are from NASA, and so valid and reliable (and primary source too!)
Teacher
fretsonfire74
New Member
Yes, but the change is so miniscule to the planet because it has so much mass, that it's negligible.