What is the mass of the earth?
Planet Earth is the third largest planet in the solar system. It is also the largest in mass, diameter, and density among the terrestrial planets (this includes Venus, Mercury, Earth, and Mars). However, the Earth, for example, is 14 times inferior in mass to another gas planet, Uranus.
Few today know what the mass of our vast and immense planet is, while scientists have figured it out long ago. It is equal to 5.98 · 1024kilograms.
In our article we will tell in detail what the mass of the Earth is equal to and how it is calculated.
Gravity, weight and weight
Gravity, mass and weight are one of the basic physical quantities, however, many people confuse these concepts. It is necessary to clarify the meaning of each of them.
- Gravity - the force that acts on any body located near the surface of the earth or relative to another body. In other words, gravity is the force with which bodies are attracted to the surface of the Earth;
- Weight is the physical force or magnitude with which the body acts on the support. Suppose if a body is at rest on the surface of the earth, then the weight is nothing but the force with which this body acts on the surface. The basic unit of measurement is Newtons;
- Body weight is a measure that measures the ability of any material body to gravitational interaction. Measured in grams, kilograms, centners, tons. Gravitational attraction or interaction, in turn, lies at the basis of the universal openness of I. Newton.
Measuring the mass of the Earth is a long historical process, to which the minds of many of the greatest scientists have attached themselves. The size of our planet was first discovered by Eratosthenes in about 240 BC. er
For many centuries, Ptolemy's geocentric system dominated physics and astronomy, according to which the Earth was located in the center of the solar system. Only after the open N. Copernicus, I. Kepler, G. Galileo, and others. Began a detailed study of the parameters of the planet Earth. The basic laws of dynamics were discovered - the laws of I. Newton, which initiated the measurements of the mass of the Earth.
The mass of the Earth was first measured in the 18th century by a British chemist G. Cavendish. For his experience, he used the installation of torsional weights with lead balls attached to the ends. Alternately bringing to these balls two large lead balls,the scientist determined how many times the force of attraction of a small ball to a large one differs from the force of attraction of the Earth. The mass of the Earth according to calculations turned out to be 6 · 1021kilograms. This number is very close to the value of the mass of the Earth, already adopted in our time, it is about 5.98 · 1024kilograms.
The formula for calculating the Earth according to the basic laws of dynamics is as follows:
- M = q · r2/ G, where:
- M is the mass of the Earth;
q - gravitational acceleration or acceleration of free fall, attached to the body by gravity. It is measured in meters per second and depends primarily on the latitude and time of day on the surface of the planet Earth. In physics, the figure of 9.8 is taken for gravitational acceleration;
- r is the radius of the earth
G is the gravitational constant that determines the gravitational interaction of material bodies on the surface of the earth. In the international system SI G = 6.6742 · 10−11m3from−2kg−1.