Gravitational pull

Tidal Power. Tidal power is caused by the gravitational pull of the sun and especially the moon, as they pull at the earth. Reacting to this pull, the ocean s waters rise, causing a high tide where the moon is closest. The difference between low and high tide can range from a few cm to several meters. Harnessing tidal power for electricity production by the use of dams requires a tidal difference of at least 4.5 m, a requirement met at few locations in the United States. Thus, the principal demonstration sites of tidal power are in Canada, China, and France. 

The gravitational pull toward the earth is balanced by the diamagnetic force and the buoyant force. In addition, the nuclear paramagnetic force ought to act on the body. (B) Upon inversion of the nuclear magnetization, the body should move to take the balance of the forces. 

Mass is a measure of the amount of a sample. Weight is the measure of the gravitational pull on this amount of sample. On the surface of the Earth, a weight measurement is taken to be the same as a mass measurement, utilizing the same units, although technically they are not the same. 

The term capillary action describes the upward movement of a fluid as a result of surface tension through pore spaces. The fluid can rise until the lifting forces are balanced by gravitational pull (see Figure 3.28). The rise of fluid in a small tube above the water table surface, as previously discussed in Chapter 3, can be described using Equation 3.13. Lifting of fluids above the water table is a true negative pressure compared with atmospheric pressure (also described as soil suction). In soil situa-... 

There is very little hydrogen as H2 in the attnosphere of the Earth. It was not always so. There is convincing evidence that the atmosphere of the very early Earth contained much hydrogen. However, the gravitational pull of the Earth for this very light gas is quite weak and atmospheric hydrogen has long since escaped into outer space. 

Was this your answer Yes, absolutely The moon exerts a downward gravitational pull on any body near its surface, as evidenced by the fact that astronauts were able to land and walk on the moon.This NASA photograph shows an astronaut jumping. Without gravity, this jump would have been his last. 

The moons gravitational pull on our planet is uneven. The side of Earth closest to the moon experiences the greatest pull, and the side farthest away experiences the weakest pull. The result of this uneven pull is a subtle, planetwide elongation of our oceans. As the Earth spins underneath this elongation, Earthbound observers notice a perpetual rise and fell of sea level. These are our ocean tides, and they can be harnessed for energy. 

FIGURE 5.17 A liquid is pulled up the inside of a tube by the surface tension and climbs until the upward force is balanced by the downward gravitational pull of the mass of liquid (regarded as a cylinder). 

The earth was formed by a process of accretion about 4.6 billion years ago. Initially it was a molten mass lacking the gravitational pull to retain its gases at the prevalent elevated temperatures. And yet, within a mere 700 million years of the planet s birth, as calculated from the isotopic record of sediments, cellular life almost certainly existed. What raw materials were available to bring about this amazing turn of events What were the sources of energy used to drive the necessary reactions Where did the important reactions take place Was it in the atmosphere, in the oceans, on dry land, or all three ... 

The picture would be similar to that of an orbiting satellite, the gravitational pull being replaced by electrostatic attraction. 

In a planetary system, the centripetal force is provided by the gravitational pull of the Sun. In atoms, this force comes from electrostatic interaction... 

Lights) seen shimmering in the sky above the North Pole. Stars are extremely large, hot, dense, balls of plasma. Large stars have an immense gravitational pull and can have surface temperatures up to 50,000 K (almost 90,000°F). 

Escape velocity is defined as the velocity uesc needed for an object on the surface of a planet or satellite to escape its gravitational pull. This means that the total energy (kinetic plus potential, where the potential energy as r —oo vanishes, as in Equation 3.10) is at least zero. 

Terminal Velocities—If the density of the particle and fluid are p and po, respectively, and if the diameter of the particle is some arbitrary linear measurement, the gravitational pull F on the particle is... 

In the special case of a fluid rising in a capillary tube we have the following situation. The upward pull due to surface tension must balance a column of liquid with height, say h, and density p0. Since the tension is exerted along the contact of the liquid with circumference of the tube, then the total upward pull due to this tension is 7r Dcc where Dc is the diameter of the capillary and a the surface tension. This upward pull must equal the downward gravitational pull on the mass of... 

Size analysis is based on sedimentation of particles as a function of their size due to gravitational pull or by using a centrifugal force. Can measure particles in the size range 0.01-100(xm. 

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