The magnitude of the gravitational field strength near Earth's surface is represented by

The magnitude of the gravitational field strength near Earth's surface is represented by approximately .

Explanation:

Let be M and m the masses of the planet and a person standing on the surface of the planet, so that M >> m. The attraction force between the planet and the person is represented by the Newton's Law of Gravitation:

Where:

- Mass of the planet Earth, measured in kilograms.

- Mass of the person, measured in kilograms.

- Radius of the Earth, measured in meters.

- Gravitational constant, measured in .

But also, the magnitude of the gravitational field is given by the definition of weight, that is:

Where:

- Mass of the person, measured in kilograms.

- Gravity constant, measured in meters per square second.

After comparing this expression with the first one, the following equivalence is found:

Given that , and , the magnitude of the gravitational field near Earth's surface is:

The magnitude of the gravitational field strength near Earth's surface is represented by approximately .

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me