What is Escape Velocity?
Escape velocity refers to the velocity required on a particular body for it to counteract the effect of gravitational force that would make it slow down and return back to its origin. This concept of physics can be easily understood when an object or body is pushed up in the air. Normally, this particular object will continue to go up until it will be overcome by the effect of the gravitational force that will make it stop rising and start falling back down. But since the amount of gravitational force will decrease as the distance of the object from the Earth’s core increases, one just needs to make sure that the velocity at the origin, before thrusting the object upwards, is high enough to counter the effect of gravitational force allowing this particular object to continue its direction upwards. In this case, the velocity at the starting point is called the “escape” velocity because in literal terms, this is the velocity needed by the object in order to “escape” or “break free” from the negative pull of gravity that would otherwise make the object return back to Earth.
A simpler explanation of escape velocity is in the case of launching rockets into space. By comparing light objects that have minimal escape velocities to a rocket’s propulsion into space, one will have a good idea of the concept of this type of velocity. Throwing a baseball up in the air involves minimal speed and will not be able to counter the effect of the gravitational force. In this case the ball will simply drop down back to earth. In the case of launching rockets into space, the engine and boosters will allow for the rocket to be pushed up into the air at velocities high enough that the rocket can somewhat resist the pull of gravity and continue its upward surge and eventually reaching a point where it can follow an orbital path without having to “fall down” back to Earth.
Escape velocity on the Earth is calculated to be at 11.2 kilometers per second. This just means 11.2 km/s is the required velocity for an object to be able to break free from the Earth’s gravitational pull.