Gravitational Force

In the first simulation, we can see that all five balls are falling at the same time. You might be wondering how this is possible. Well, to understand this, lets take a look at the second simulation. The second simulation seems to be more like a real-life scenario. The bowling ball falls first, with the cricket ball and the golf ball following next, and then the basketball, and finally the ping pong ball. This is because, the bowling ball is the heaviest (the most mass) and the densest (the most mass per unit area). Even though, the cricket balls and golf balls are smaller in size, they are much denser than the hollow basketball that is filled with air, which means their masses are concentrated in a small area, so they fall faster and air resistance doesn’t affect them as much as it does for the basketball and the ping pong ball. The basketball and the ping-pong ball are hollow, so other than the material making up the surface and the internal layers, they are filled with air, and because of this, they are lighter, and so air affects them more. Since, the basketball is heavier and made of a thicker material, it falls faster than the ping-pong ball, which is extremely light. THIS IS IN THE PRESENCE OF AIR.

This is how balls drop in real life from a large height. However, in the first simulation, we can see the same balls, but they seem to be reaching the ground at the same time. How is this possible? Well, interestingly, it turns out if there was no air, or medium of any sort around us, which is called vacuum (space is vacuum by the way), then regardless of their masses, if the balls were released at the same height, they would reach the ground at the same time. This is what has been shown in simulation number one.

Did you know?
Have you ever wondered what the difference between mass and weight is? Well, mass is a measurement of how much matter an object has. This doesn’t change no matter where you go, another place on Earth, another planet, or even another universe (if you manage to do so). Weight, on the other hand, is a measure of the gravitational force on an object. It doesn’t stay the same all the time. In more scientifical terms, it is the product of mass and acceleration due to gravity, so it changes as the acceleration due to gravity changes.

Gravitational force

Gravitational force is necessary for holding our entire universe together. We could not live on Earth without gravity.

What exactly is gravitational force?
Simply put, gravitational force is a force of attraction that objects with mass have. They attract other objects of mass with this force, and no matter what body, it will always produce this force of attraction. The gravitational force between two bodies depends on two factors: the mass of the body and the distance between the two interacting bodies (the main body and the other body that the first body is affecting). Mass refers to the amount of matter in an object.

But wait a minute, when we say it depends on mass, that means it depends on the object as an individual thing. But we also said it depends on distance, which means that the gravitational force between two objects depends on both objects. So, what exactly does it depend on then? Is it a force that depends on each body individually, or two bodies? Turns out, the gravitational force is influenced by both. According to Newton’s law of universal gravitation, every object in the universe attracts every other object with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres.

This means that the gravitational force an object exerts is not just a property of that object alone. It’s a relationship between that object and another object. The force is stronger when the objects are more massive and/or closer together and weaker when they are further apart and/or smaller.

So, while each object does have its own gravitational force, the strength of that force in any given situation depends on the mass of the other object and the distance between them. This is why we can feel the gravitational force between us and the Earth (a very massive object), but the force between us and smaller objects is too weak to feel.

In summary, gravity is a mutual force that depends on both objects involved, not just one. It’s the interaction between two objects that results in the gravitational force we observe.

What is the difference between gravity and gravitational force? Are they the same thing?

No, they are not the same thing. The major difference between gravitation and gravity is that gravitational force occurs between two different or the same objects. While the force of gravity acts between the earth surface and any object. The force of gravitation acting between two objects is quite weaker as compared to the force of gravity. The Gravitational force can either be attractive or repulsive depending on the direction of movement. But, the force of gravity is only attractive, as the object is very small in mass compared to the mass of earth. Thus, the object gets attracted to the Earth’s surface. Gravitational force is a universal force, whereas the force of gravity is a derived one and it may vary from one place to another.

When we drop two objects, if there was no air resistance (or there was no air at all), regardless of the mass of the objects, if the objects were dropped from the same height, they would all reach the ground at the same time. This is because the acceleration isn’t dependent on the mass at all. Here’s the mathematical representation (for more advanced learners):
ma = (G Mm)/r^2
⇒ a = (GM)/r^2

Here, the mass of the body cancels out, leaving the above formula. Since all of the components in the above formula are constants, this is why acceleration due to gravity is also a constant.

Gravitational force and our solar system:

According to what we have learnt so far, when we have an object of a huge mass such as the Sun, and another of huge mass, but comparatively smaller like the Earth, the Sun will attract the Earth towards it. So, why haven’t the Earth and the Sun collided yet? This is because the Earth DOES get attracted towards the Sun, but because of its high speed of 67,000 mph, it keeps missing. Therefore, because of the constant attraction, it cannot go off in a straight line, so instead, it moves around the Sun in an orbit. So, that if Earth’s speed reduced or if it stopped, it would indeed start moving to the Sun and later on collide.

The sun's gravity keeps Earth in orbit around it, keeping us at a comfortable distance to enjoy the sun's light and warmth. It holds down our atmosphere and the air we need to breathe. Gravity is what holds our world together. However, gravity isn’t the same everywhere on Earth. Gravity is slightly stronger over places with more mass underground than over places with less mass.

The Four Fundamental Forces:
- Gravitational force

- The weak force: The weak force, also called the weak nuclear interaction, is responsible for particle decay.

- Electromagnetic force: The electromagnetic force, also called the Lorentz force, acts between charged particles, like negatively charged electrons and positively charged protons. Opposite charges attract one another, while like charges repel. Electromagnetism is a process where a magnetic field is created by introducing the current in the conductor. When a conductor is electrically charged it generates magnetic lines.