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relation between thrust and velocity
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can some one help me out. what's the equation to describe thrust and velocity? velocity that i meant here is the moving speed in x direction.
p6
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Re: relation between thrust and velocity
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by MiCHiYo μ
on 2006-12-04 20:55:18 (edited 2006-12-04 22:09:30)
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okay... Thrust is a force which signifies the change of momentum in time. It is highly related to Newton's third law, where for every action, there is an equal and opposite reaction. This is because, as gas is accelerated, the vehicle, which should be an airplane, accelerates in the opposite direction. As we know, F=ma, where F is force, m is mass, and a is acceleration due to gravity. Therefore, thrust has a general equation of  where F is the change in momentum with the change in time (ergo, force), m is the momentum of the object, v is the velocity, and t1 and t2 is the change in time. ...this is the simplest way i can explain it, basing on what i've learnt. for more information, go to NASA's website. -michiyo- 
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Re: relation between thrust and velocity
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Maybe I'm wrong, but isn't "m" the mass and "V" the velocity? As in p=mv (momentum equals mass times velocity) Its just, I've always know momentum to be "p"....
Wise Man says: "Take a dog off its leash and it will wander."
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Re: relation between thrust and velocity
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by MiCHiYo μ
on 2006-12-04 22:08:59
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well, letters always go around and change around, but allow me to edit one thing up there. *edits the F part* there. XD at least you made me realise how annoyingly repetitive i was. =P anyhow... let's see what gendou-sensei has to say about it. ^___^ -michiyo-
beware. the QueeN oF SiGGieS is here. kill that mr. scrolly or your siggy goes BAI BAI. it's solidarity month! let's be united! +[-- GeNDouNiaNS: i am half-back! visit my blog by clicking on the siggie banner! updated: 12.07.07 --]+
~*..:: i'm never going to give up... if i do, then it wasn't worth trying. ::..*~
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Re: relation between thrust and velocity
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From Newton's second law of motion, we can define a force F to be the change in momentum of an object with a change in time. Momentum is the object's mass m times the velocity V. So, between two times t1 and t2, the force is given by: F = ((m * V)2 - (m * V)1) / (t2 - t1) -From the NASA link If "m" is equal momentum, then the formula could be made simpler: F = ([mV2]2 - [mV2]1) / (t2 - t1) Where m is mass and V is velocity, as mass is much easier to find than momentum.
Wise Man says: "Take a dog off its leash and it will wander."
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Re: relation between thrust and velocity
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by
on 2006-12-05 00:07:01 |
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For thrust, is a force (as Michiyo said) and the explanation if it comes from the Newton third law of motion (action, reaction). As I know, what you have said is correct, but m is mass and V is velocity.  and for velocity... there are a lot of expression for it, depending on the type of movement   |
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Re: relation between thrust and velocity
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thanks for the reply. for the time being, let me have a look at it first. if there's something i don't understand, please teach me again. again, thank you. p.s. thanks for the nasa link.
p6
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Re: relation between thrust and velocity
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by
on 2006-12-07 09:57:13 |
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I'm glad we helped man... although I'm even more happy because this was the first time for me replying in this section =D... I'm not used to come here very often. |
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Re: relation between thrust and velocity
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More simply , I believe "F=(Delta)p/(Delta)t" would work. Sorry, my computer dosn't have the sign for "Delta"
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Forty and two years old was Ahaziah when he began to reign. - 2 Chronicles 22:2 |
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Re: relation between thrust and velocity
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Mv-Mu (mass x Final velocity - mass x initial velocity) = I (Impulse). Impulse measures the change in momentum. Thus, Thrust is defined as I/t. (by convention... v is final velocity and u is initial velocity) Obviously, F = ma = (mv- mu)/t because we can take m from both sides and we are left with a = (v-u)/t.  |