Gravity

The gravity on Venus is about 91% of Earth's gravity, on Mars it is about 38%, on Uranus it is about 89%, on Sedna it is about 0.6%, and on Neptune it is about 114% of Earth's gravity.

Isaac Newton began the definition of gravity. Later work refined the definition, with important milestones in the work of Albert Einstein in the early 20th Century. The process of defining gravity continues to this day.

There are typically four forces described in physics:

Gravity

Electromagnetic

Weak

Strong

Sometimes the electromagetic and weak forces are referred to as "electroweak"

I'd like to elaborate on this actually. If you consider the macroscopic scale there are also other consolidated forces engineers take into account to simplify problems such as drag forces, damping forces and etc.

Yes, gravity affects a parachute by pulling it towards the Earth. As the parachute falls, air resistance creates drag, which slows down the descent due to gravity pulling it downward. The design of the parachute and its size also play a role in its rate of descent.

The specific gravity of a substance depends on the acceleration due to gravity. Since the gravity is lower on the moon than on Earth, the specific gravity of mercury will be different between the two. On the moon, the weight of mercury would be less than on Earth due to the weaker gravitational pull, causing its specific gravity to be different.

No, the center of gravity of a meterstick is not always located at the 50-cm mark. The center of gravity of an object is the point where its weight is considered to act. For a uniform meterstick, the center of gravity will indeed be at the 50-cm mark because of its uniform density distribution, but if the density distribution is not uniform, the center of gravity could be located at a different point.

It is a system provided to reduce vibrations caused from helicopter Rotors or Blades. It is passive Type of Reduction system. It reduces mainly 4/rev vibrations. Generally, this system is fixed in between the Rotors and Fuselage.

Aris system consists of spring, Diaphragm, Pendulum. Spring is for Providing Stiffness & Diaphragm for Transfer motion of spring to Pendulum. Pendulum is to Dissipate Energy.

Something can only be weightless in zero gravity.

The Specific Gravity (Gs) is needed for various calculations purposes in Soil Mechanics, e.g. void ratio, density, and unit weight.

For Sandy soil, i.e. soils mostly made of quartz, Gs can be accurately estimated to be about 2.65, whereas for silty and clayey soils, it may vary from 2.6 to 2.9.

Acceleration due to gravity is the force that pulls objects towards the Earth. It causes objects to accelerate at a rate of 9.81 m/s^2 towards the ground. This acceleration is responsible for the feeling of weight that we experience, and it also affects the trajectory of objects thrown or dropped.

It has slightly different values in different places on the earth. It's

generally between 9.75 and 9.85 meters per second2 anywhere .

Gravity settling chambers are used in industries to remove particulate matter from gas streams. They rely on the force of gravity to allow the particles to settle out of the gas stream and collect at the bottom of the chamber. This helps to clean the gas stream before it is released into the environment.

-- It always attracts, never repels.

-- The gravitational force is always equal on both of the masses that attract each other.

The formula you are referring to is for potential energy: Potential energy = mass x gravity x height. This formula is used to calculate the energy an object possesses due to its position above the ground.

The strength of gravity is determined by the mass of the objects involved and the distance between them. The greater the mass of the objects and the closer they are to each other, the stronger the gravitational force between them.

Yes. It results in a force that has a magnitude and a direction, and this is the definition of a force vector.

Specific gravity is measured by comparing the density of a substance to the density of a reference substance (usually water). It is typically determined using a hydrometer or a densitometer. The specific gravity of a substance is a unitless value that indicates how much denser or lighter the substance is compared to water.

everything uses gravity! if gravity was absent we all would be flaoting!!

The greater the mass of an object, the greater its inertia. This means that heavier objects are more resistant to changes in their motion, such as stopping or changing direction, compared to lighter objects. In simpler terms, the more mass an object has, the more force is needed to accelerate or decelerate it.

Helicopters do not defy gravity. They generate lift through their rotating blades, which pushes against the force of gravity to keep them airborne. Without this lift, helicopters would fall to the ground like any other object under the influence of gravity.

Gravity causes liquids to be pulled downward due to the force of gravity. This results in liquids settling at the bottom of a container and taking the shape of the container that holds them. Gravity also affects the flow and movement of liquids, influencing their behavior in various environments.

To keep a sled accelerating downhill, the force of gravity must be greater than the force of friction acting against the sled. This allows gravity to overcome the frictional force and propel the sled forward.

Sir Isaac Newton developed the theory of gravity and relativity. He decided that there was a force that drew objects toward the centre of the earth but at the time he made his observations he didn't know what the power of this force was. In August 1684, when Newton was 41, Halley, a good friend and the man Halley's Comet is named after, put a question to Newton: supposing an inverse square law of attraction toward the sun, what curve would a planet make? Newton then said an ellipse: he had calculated this a long time ago (when he was 23). He started working again on it and several months passed before providing Halley with a proof.

He had great difficulties because there was no vocabulary associated with this work. So, he invented it: he defined Quantity of matter as mass, and Quantity of motion as the product of velocity and mass. He then send Halley a 9-page treatise "On the motion of bodies in orbit". Halley was excited and asked Newton for more pages, but Newton was not finished. Eventually he established that this mysterious force was gravity.

Albert Einstein picked it up from there. He was 21 years old at the turn of the 20th century, 1900. By then Newton's theory of motion gravity had dominated physics, providing the tools to explain the everyday phenomena in our world and explaining any almost physical problem imaginable. However, there were tiny discrepancies that did not fit in the theory. This was a typical case were in order to explain these small discrepancies a major breakthrough is required; a huge jump in our understanding of the world.

In terms of experiments, the astronomers had found that the orbit of Mercury around the sun is not a fixed ellipse; it moved slightly as the years passed. In Newton's theory, this result was not predicted since all the ellipses should be fixed. It was then thought that because Mercury is so close to the huge mass of Sun, it might be affected in a gravitationally different way. Einstein managed at 1916 to find a satisfying theory that would explain this fact, but in order to get a glimpse of it we should go a few years back and look at his theory of special relativity first.

In 1905, at the age of 26, Einstein managed to extend Newton's theory for the motion of bodies at high speeds; by assuming that the speed of light is constant no matter how one is traveling (at a constant speed) he derived an extension to Newton's equations which holds true for every speed, not only for low ones. Newton was still correct in that limiting case. These results however were valid only if the objects are moving at constant velocity; a replacement of Newton's send law which describes what happens when an object is accelerated was yet to be found. Einstein was the first person responsible of extending his theory of zero acceleration to a theory of non-zero acceleration.

He stated that the gravitational field is not actually a force as Newton has described, but instead a curvature in space. To put it in simple words, the bodies are affected by gravity not because of a force directly exerted on them but because space is curved and therefore they have to follow space's grid. The presence of mass or energy does not affect the bodies directly; it affects the space first, and then the bodies move in this curved space. Earth always moves in a straight line (not in the Euclidian sense though). The presence of sun curves space, and therefore curves this straight line and forces earth to appear to be moving in an ellipse.

The 'surface' acceleration of gravity on Neptune is 11.15 m/s2 .

That's about 14% greater than on the Earth's surface.

If you weigh 200 pounds on Earth, then at the depth in Neptune's gaseous mantle

where the pressure is equal to Earth's sea-level atmospheric pressure, you'd weigh

about 228 pounds.