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Katherine johnson nasa code2/28/2023 Naturally, the same reasoning applies to other planets as well. That is, a rocket would have to accelerate to that speed to break free of Earth’s clutches. Stick in figures for each of those and for Newton’s constant G, and we find that v is just over 11km/second. Note that this velocity is dependent solely on the mass and size of the Earth. Some manipulation later, we get v = sqrt (2GM/r). Thus we equate the two energies: GMm/r = mv 2/2. Because that’s when it will be able to break that hold. If you think about it, we want the rocket to be moving fast enough that its kinetic energy equals the potential energy inherent in gravity’s hold on it. (For here and now, trust me about these energy formulae). When the rocket starts moving, its kinetic energy is a function of its mass m and its velocity v: mv 2/2. In effect, this tells us how powerfully gravity is acting on the rocket. This involves the mass of the Earth (M), the mass of the rocket (m), the size of the Earth (its radius r), and Newton’s gravitational constant, G, which is a measure of how strong gravity really is (actually pretty weak): the rocket’s potential energy is GMm/r. (Not just rockets: All of us do this energy conversion when we go from being at rest to moving). A rocket at rest has a certain inherent potential energy that it converts into kinetic energy when it starts moving. The way to understand this is, first, to remember those hoary old terms, potential and kinetic energy. Let’s start with easily the most straightforward of them, the escape velocity from the Earth. So as my own tribute to a fine mind, let me give you a flavour of some of the calculations above. Somehow the calculations just got done, and the flights just happened, and few outside Nasa thought to ask, “but how did you get all this right?" But especially in Nasa’s early days, their human computers worked in the shadows, never really part of the agency’s public image. After all, she was a critical part of plenty of Nasa’s missions: the first American in space, Alan Shephard’s 1961 flight John Glenn’s orbit of the Earth in 1962 the Apollo lunar missions including Apollo 11’s Moon landing in 1969 and later even the Space Shuttle. It’s a pity, if not very surprising, that it took a 2017 Hollywood film ( Hidden Figures) for the wider world to come to know of Johnson-and indeed, others like her. That’s Katherine Johnson of the National Aeronautics and Space Administration (Nasa). This week, one of the best known such computers died at 101.
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