Slingshot Effect (1 Viewer)

[ronnknee]

I understand that probes utilise the gravitational attraction of another planet like Venus to speed it up when sent to outer space.

Can someone explain how when the probe passes Venus, its speed is reduced relative to Venus but increase relative to the Sun?

 

[twilight1412]

I understand that probes utilise the gravitational attraction of another planet like Venus to speed it up when sent to outer space.

Can someone explain how when the probe passes Venus, its speed is reduced relative to Venus but increase relative to the Sun?

please dont EVER use the word 'speed'
the word your looking for is velocity, as for how its increased relative to the sun if you draw its in and out vectors it will turn out to be a triangle and hence the resultant will end up larger or smaller depending on whether or not you wanted it to slow down or speed up =)
larger velocity vector shows an 'increase' in the velocity although this is due to the direction and not the magnitude in fact the magnitute remains the same

as for the speed being reduced that is a load of crap =)
infact the magnitude of the velocity is the same and the direction is even the same relative to the planet =) *think about this one*

what infact happens is that it steals some angular momentum =)
and thats how it achieves its change in direction
although this does in fact slow down the spin velocity of the plant
the mass difference between the planet and the ship is so large that the amount is negligable =)

 

[Forbidden.]

Yes, don't use speed but do use angular momentum.
The spacecraft gains energy from Venus relative to the sun however relative to Venus the energy and orbital velocity loss is negligible.

You must consider frames of reference which will be studied later in the sub-topic 'Special relativity'.

 

[twilight1412]

thanks for the support forbidden =)
i wasnt really sure since i havent looked it up in nearly a year ..

should probably revise my space again sometime soon but quanta is just @_@

 

[Forbidden.]

thanks for the support forbidden =)
i wasnt really sure since i havent looked it up in nearly a year ..

should probably revise my space again sometime soon but quanta is just @_@

Why is it the option topics are the hardest to remember ?
I still don't remember a lot in Astrophysics.

The option topics in Chemistry and Physics have craploads of information compared to the core topics.

 

[twilight1412]

Why is it the option topics are the hardest to remember ?
I still don't remember a lot in Astrophysics.

The option topics in Chemistry and Physics have craploads of information compared to the core topics.

its probably because they get more marks to screw you over with =P
that and because i believe we had less time to learn it?

 

[shredinator]

Yeah, I don't get what's with learning an option like a month before the HSC exams.

 

[twilight1412]

well i dno about you but i think i had a term not a month but that term had at this crap in it =S

the time you get comes down to how fast you finish your other sections really

 

[JulzMighty]

firstly, in classical physics (which is what we apply in our exams except for specific special relativity questions) gravity has nothing to do with angular momentum. it would only do so if the probe got into contact with the planet (or perhaps just its atmosphere, which they wouldn't allow because this would diminish the effects of the slingshot manoeuvre).

secondly, speed describes the magnitude of velocity, so why not ask about the speed? this just means the question isn't concerned about the change in direction.

julz

 

[Ozza]

I understand that probes utilise the gravitational attraction of another planet like Venus to speed it up when sent to outer space.

Can someone explain how when the probe passes Venus, its speed is reduced relative to Venus but increase relative to the Sun?

K, you can actually think about this rather logically...

If the probe passes Venus, the gravitational pull of Venus pulls the probe towards it slighty, which makes it appear to go a little bit slower to Venus. However, if it's pulling it towards Venus, it's still pulling it away from the Sun, hence it's reduced relative to Venus, but increased relative to the Sun.

And I do medical physics = bludge

It's not that hard to my mind... just basically a rehash of ideas to implementation, add to that just knowing how ultrasound, X-rays, PET and MRIs work... sounds like a lot.. but it's really basic.

 

[appleide]

We did Astrophysics right after Space, so spent enough time on it.

Here's my take on the Venus and the Sun and the craft:
As the craft approaches Venus, it is attracted by gravitational force into its orbit, and as the craft orbits Venus, its velocity relative to Venus is also reduced.

Remember, Venus is orbiting the Sun at over 30km/s. Because the craft is 'hugging' Venus a its velocity relative to Venus is slowed, it also follows Venus in orbiting the Sun, increasing its velocity relative to the Sun.

Kinda like a fly intercepting you as you are sprinting and landing on your back to gain speed.