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decibel
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Originally posted by StephenPrivitera
Is it derived from the fact that F=ma and planets travel in ellipses?
EDIT:
This site used Kepler's Laws to derives Newton's
http://www.physics.ubc.ca/~outreach/phys420/p420_95/tracy/universal.html [/B]
I guess I am not aware of Galileo's work.Originally posted by Ambitwistor
Given Galileo's work, Newton knew that the gravitational force on a body had to be proportional to its mass.
Do you happen to know how to do this? I can't seem to figure it out for myself.Originally posted by Ambitwistor
He then calculated the orbits that would result from such a force law
Originally posted by StephenPrivitera
The graph of the gravitational potential U=-GMm/r looks like a hyperbola to me. If E<0, then certainly the particle is bounded in that it will not reach infinity.
But what does this say about the shape of the orbit?
Also, the fact that E<0 does not put a lower bound on r (except of course r>0). What about the graph indicates that the U of the particle will oscillate?
Scientists measure the weight of a planet by using Newton's law of universal gravitation, which states that the force of gravity between two objects is directly proportional to their masses and inversely proportional to the square of the distance between them. By measuring the gravitational force between a planet and a known object, such as a satellite, scientists can calculate the planet's mass and therefore its weight.
Scientists use a variety of tools and instruments to measure the weight of a planet. These include telescopes, which are used to observe the movement of objects in the sky and determine their mass, and spacecraft, which can collect data on a planet's gravitational pull. In addition, mathematical equations and computer simulations are used to calculate the weight of planets.
The accuracy of the measurement of a planet's weight depends on the quality of the data and the methods used. In general, modern techniques can determine a planet's weight with a high degree of accuracy, usually within a few percentage points. However, factors such as the planet's composition and the presence of other objects in its orbit can affect the accuracy of the measurement.
Yes, there are several challenges in measuring the weight of a planet. One major challenge is the presence of other objects in the planet's orbit, such as moons or debris, which can affect the gravitational force and make it difficult to determine the planet's weight. Additionally, the composition and density of a planet can also impact its weight, making it challenging to accurately measure.
The weight of a planet is an important factor in many areas of scientific research. For example, a planet's weight can provide valuable information about its composition, history, and formation. It is also used in astrophysics to study the dynamics of planetary systems and their interactions with other objects in the universe. Additionally, the weight of a planet can be used in space exploration to determine the feasibility of a mission and the resources needed for a spacecraft to reach and orbit the planet.