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Let's back up a bit and then it'll be clear why there is a demand for some serious speed in a given direction (velocity) to get the heck out of the gravitational well we're stuck in - and stay up. Ready? Let's jump. Grab a nice big rock, hold it out, and then drop it. What happens? Right. It falls to the ground. Take it up on a tall building and repeat the experiment (safely). What happens? Right again. It falls. Take it up in a plane and drop it. It falls. Now take it up a couple of hundred miles and let it go. What happens? Surprise! It falls. Why wouldn't it? The earth hasn't let go of it. Gravity is still pulling on it. What's up with that? Let's look as what we need to keep an object up there. If we get something big really high and outside the atmosphere, we need to do something to "break the grip" of gravity. (It hasn't let go.) It's already cost us a ton of money to get it up that high 'cause rockets are really expensive. What we need is some "sideways velocity" to keep our payload up. Gravity hasn't let go, so our rocket needs to shove things sideways as well as up. We have our rocket pitch over (change course) and begin that sideways acceleration not long after liftoff. That's what takes it "down range" and away from the launch pad (not just up). Our rocket is moving up and sideways; it's gaining altitude and is accelerating in a lateral direction. Picture our object high above the atmosphere. Way up. Picture the object stopped in time and space. Now picture the object one meter closer to earth because of the effect of gravity, but at the same time, picture it one meter at a right angle to "down" in the direction of orbit. Our object remains at the same altitude it was, but is "farther over" from where it was because of the lateral acceleration we gave it. Now another meter down and another meter farther over. Same result. It's still at the same altitude, but farther over. It's like the object is "stepping" around the earth. See how that works? What actually happens can be described exactly like this in infinitely small steps! (Welcome to the calculus!) Our object is in orbit because enough lateral acceleration has been applied during the burn of the main engines to give the payload "just the right amount" of "sideways" motion. It's high enough and moving fast so that its lateral velocity and gravity are in a "steady state" or are "balanced" and our payload stays in orbit. "Houston, we've achieved orbital insertion."
Wiki User
∙ 16y ago
Wiki User
∙ 16y agoBecause it is heavy and gavity is pulling it back down, therefore, it needs a big force to leave the ground.
Wiki User
∙ 13y agoBasically a gigantic amount of combustion to push it off of the ground.
Wiki User
∙ 14y agoYou need to get going 17,500 miles per hour to escape Earths gravity.
Wiki User
∙ 13y agoThe thrust must be greater than the total weight of the load to be lifted.
Wiki User
∙ 14y agoA force equal to or greater than its weight.
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How did you explain conservation of momentum when a rocket ship takes off?
Momentum P of a body with mass m and velocity v is given by:P = m∙vNewton's first law of motion establishes conservation of momentum on abody as long as there is no net force applied on it.Let's assume our Rocket Ship is about to be launched from the surface ofa planet with no gravity force, so we can leave out the influence of thisforce from the discussion.At time t ≤ 0 from launch, the Rocket Ship's velocity v is zero, and soits momentum P is also zero.When the Rocket Ship starts his motion upwards, the initial system (theRocket Ship), is now conformed by two subsystems: The Rocket Ship goingup and the exhaust gases being sent down.To give a simple view of what happens, lets assume that the massof the exhaust gases is expelled at a constant velocity vg through the wholeprocess till the Rocket Ship's engine stops. Then the final condition ofmomentum would be:P = mR∙vR + mg∙vg = 0where mR and mg are the final Rocket Ship's mass and the total mass ofexhaust gases expelled respectively, and vR the Rocket Ship's final velocity.You have to realize that the vectors of velocity VR and Vg will have oppositesigns.If we now would want to include the planets gravity force, this willbe affecting the momentum of the Rocket Ship by producing an accelerationin the opposite direction of its velocity. If we now think of the originalsituation of Rocket Ship and planet at rest, when the Rocket Ship ispushing away from the planet the gravitational attraction between theRocket Ship and planet works both ways. And so the lose of momentumby the Rocket Ship because of the gravitational force is compensated bythe planets lose of momentum in the opposite direction !.
Why don't we notice the difference between mass and weight on earth?
Because the atmosphere is such a thin layer and we rarely leave it. We stay at roughly the same elevation so the force of gravity is relatively unchanged. On the peak of Mt. Everest, we might measure a tiny decrease in weight. Likewise, in the deepest mine, we might as well.
Where is the magnetic force the greatest on a magnet?
The magnetic force of a magnet is strongest at its poles. This is because the field lines of the magnetic field are most concentrated at the poles where they enter and leave the magnet. At the poles the magnetic field is strongest and the force is the greatest. The north pole is where the magnetic field lines enter the magnet. The south pole is where the magnetic field lines leave the magnet. The magnetic field lines are most concentrated at the poles. The magnetic force is greatest at the poles.
Why do new tennis balls bounce higher than old tennis balls?
The polymeric materials in new tennis balls have a higher coefficient of restoration, so they tend to spring back into shape easier. With time and exposure to atmosphere, the compounds that keep the ball soft volatilize and leave into the atmosphere.
When forces act in opposite direction?
When two equal forces act in opposite directions, they are called balanced forces, and no motion takes place. If they are unequal, than the weakest force is cancelled out, along with an equal amount of the strongest force. For example, if an object is being pushed on opposite sides with 7 and 10 newtons of force, then the 7 newton force will be entirely cancelled out, along with 7 newtons of the 10 newton force. This will leave a net force of 3 newtons acting on the object. If there is a net force (also called an unbalanced force), then motion will take place.
What is the factor in determining the amount of thrust a rocket requires to leave the earths atmosphere?
Payload weight
What is the main factor in determining the amount of thrust a rocket requires to leave the Earth's atmosphere?
Payload weight.
What is the main factor in determining the amount of thrust a rocket requires to leave the earths atmosphere?
Payload weight
What is the main factor in determining the amount of thrust a rocket requires to leave earth atmosphere?
Payload weight.
How do astronauts leave the earth?
astronauts leave earth by the liftoff of the space shuttle and rockets, it is called force of the rocket. The engine starts and liquid fuel comes out of the rocket and pushes them up.
How the propulsion of jets and rockets is an application of newton third law motion?
For every action (force) there is and equal and opposite reaction (force). When fuel is burned in a rocket or jet, the hot expanding gases leave the rear of the engine. The opposite is the force pushing the rocket itself forward.
9 Can someone see this planet easily or is special equipment needed?
If you are referring to the earth, then yes. Very special equipment is needed. For one, a space shuttle or rocket ship so you can leave the earth's atmosphere. The only way tp see this planet is in a picture, or from space. If you are reffering to a different planet, then you will probably need a telescope.(obviously)
Why are rockets good for space travel?
Rockets aren't necessarily good for space travel they are a necessity. You cant leave earth without a rocket... you wont be able to break through the atmosphere.
What was the first ever man-made object to leave earth's atmosphere?
Probably one of the late ww2 v-2 rockets, if not then an army redstone rocket certainly did as it was basically an enhanced v-2.
How does the rocket propel itself in space?
Regardless of what people have been taught, rockets need an atmosphere to work (no matter how weak that atmosphere is). The expanding force of the burnt propellant is what a rocket uses to thrust itself forward. The rocket is able to produce so much pressure for thrusting because of the presence of the external atmosphere the propellant has to push through, not against. (A rocket's fuel needs not push against anything).If there were no atmosphere and a very strong vacuum, the propellant would flow and expand too freely to the outside of the craft too fast, and leave the chamber without enough pressure to create thrust. (Positive flows towards negative, yet it always chooses the path of least resistance to do so).Already in earth's atmosphere, the majority of the propellant is not used for thrust but wasted through the atmosphere. If there were no atmosphere and a stronger vacuum even more would be wasted.The plume caused by a rocket's exhaust becomes more and more invisible as altitude increases. The above explanation is the reason for this situation.That's why shuttles/crafts only reach a certain altitude then orbit the planet.Thermal thrusting would become inefficient beyond a certain degree of altitude.
Would a rocket leaving the moon surface require as great a speed or force as one leaving the earth surface?
No. There is less gravity on the moon, therefore the rocket would feel less of a pull towards it than the earth. It would be easier to leave the moon than the earth.
Does the fuel effect a rocket?
Yes it does. It is the primary factor involved in lending the rocket the ability to leave the launch pad.
