A large amount of energy is needed to achieve escape velocity. Since escape velocity depends on the mass of the planet or moon that a spacecraft is blasting off of, a spacecraft leaving the moon's surface could go slower than one blasting off of the Earth, because the moon has less gravity than the Earth.
On the other hand, the escape velocity for Jupiter would be many times that of Earth's because Jupiter is so huge and has so much gravity. One reason that manned missions to other planets are difficult to plan is that a ship would have to take enough fuel into space to blast off of the other planet when the astronauts wanted to go home. The formula for escape velocity, also known as the second cosmic velocity, is derived directly from the law of conservation of energy.
At the moment of launch, the object has some potential energy PE and some kinetic energy KE. The energy at launch LE can be hence presented as follows:. When the object finally escapes, it is located so far from the planet that its potential energy is equal to zero. Also, it can have virtually no speed, so its kinetic energy is also equal to zero.
That means that the total final energy is equal to:. Because the total energy must be conserved, it means that the initial energy is also equal to zero. Simplifying the first equation, we get:.
Check our kinetic energy and potential energy calculators for more details on the topic of energy. You probably noticed that this calculator gives you an additional value - the first cosmic velocity. What is it, and what is the difference between this value and the escape velocity?
The first cosmic velocity is the velocity that an object needs to orbit the celestial body. Not Helpful 9 Helpful Kal Mondal. Not Helpful 7 Helpful 6. If I am calculating the escape velocity for Jupiter, will G still be equal to 6.
Jupiter is a gaseous planet, therefore the equation would be 6. Not Helpful 26 Helpful 4. Include your email address to get a message when this question is answered. By using this service, some information may be shared with YouTube. You can then use this to calculate escape velocity instead. Helpful 0 Not Helpful 0. Submit a Tip All tip submissions are carefully reviewed before being published. Related wikiHows How to. How to. Co-authors: Updated: December 30, Categories: Classical Mechanics.
Article Summary X To calculate escape velocity, multiply 2 times G times M, then divide that by r, and take the square root of the result.
Bahasa Indonesia: Menghitung Kecepatan Lepas. Thanks to all authors for creating a page that has been read , times. I stumbled upon this wonderful, easy-to-understand set of equations. Rated this article:. More reader stories Hide reader stories.
Did this article help you? Cookies make wikiHow better. By continuing to use our site, you agree to our cookie policy. About This Article. Robina Shaheen Oct 14, Ishani Bharadwaj Jun 21, Even a weak student in physics can understand the concept of escape velocity through these easy steps. Must go through it! A good way to think about escape velocity is to think about a deep well physicists like to think of this as an energy well.
If you are at the bottom of the well and want to get out to escape , you need enough energy to climb out. The deeper the well, the more energy you will have to expend in order to climb to the top. If you have only enough energy to get half way out, you will eventually fall back to the bottom. The escape velocity is a way of measuring the exact amount of energy needed to reach the lip of the well -- and have no energy left over for walking away.
When a ball is thrown up into the air from the surface of the Earth, it does not have enough energy to escape. So it falls back down. How might we enable the ball to escape? Throw it harder, give it more energy. How hard must we throw it? Just hard enough to get over the top, over the edge of the well.
We can find this energy directly by saying that the kinetic energy of the thrown ball must exactly equal the 'potential energy' of the well. From basic physics we know that the potential energy for an object at a height above a surface is:.
Note what extremely important parameter is not in the escape velocity equation: the mass of the moving object. The escape velocity depends only on the mass and size of the object from which something is trying to escape.
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