Potential Energy Of A Satellite

When a satellite revolves around the Earth’s orbit, it possesses both kinetic energy and potential energy. And the sum of both these energies constitutes the total mechanical energy of the object, i.e., the satellite revolving in space. Hence, the total mechanical energy of the satellite can be calculated as:

= potential energy of a satellite + kinetic energy of a satellite

The magnitude of potential energy is different for different objects in the universe. The same goes for the potential energy of the satellite. To find out the amount of energy stored in the satellite, the most common factors include the mass of the satellite, its distance from the earth’s centre, and the acceleration due to gravity. 

 Potential Energy of an Object

By the theories of physics, the potential energy of an object can be defined as the energy stored in various parts of its body depending upon the relative position of the object. In the simplest terms, we can define potential energy as the form of energy that is used to move an object from one specific position to another position. When an object is stationary, and no external force is applied to change its position at that particular moment, the energy constituted in it is defined as its potential energy.

For example, a rock standing at a fixed position since it’s not moving currently. The energy is stored in the form of potential energy, but if an external force is applied and it starts to change its position, the potential energy stored will gradually start converting into kinetic energy.

Another example can be taken of a stationary ship in a sea, while it is at rest and not getting included by any external force, be it the current of water or wind or the mechanical force applied by the sailor. The amount of energy stored in it will be termed as potential energy but only till the moment it is not moving. The moment it changes its state from rest to motion, the potential energy stored in it starts getting converted into kinetic energy.

The amount of potential energy stored in any object depends solely on its mass and hence is different for all the objects. Be it a stone of 10 mg or a ship of 1000 tonnes. The method to find out the quantity of the energy is the same for all the objects around, either on the surface of the earth or in space.

The potential energy of an object can be calculated by the given formula = m×g×h

Where m = mass of the object

g = acceleration due to gravity and

h = height or distance of the object

What is the Potential Energy of a Satellite?

Talking about all the objects in the universe, one of them which can be taken into reference for the best explanation is a satellite. When it is launched into space, there are many factors at that time that need to be carefully examined. There should even be a well-calculated mass so that there is no mechanical fault.

When we talk about the potential energy of a satellite, what it means is the energy stored into it while it was being launched, i.e., before any external force was applied to it—it was at the position of the rest then and was not moving yet. Once the force was applied, it changed its state, and the stored potential energy started to get converted into kinetic energy due to the movement caused in its body.

A manmade satellite is an object which keeps revolving around the earth’s orbit. Since the satellite is revolving, it must have kinetic energy, but in the earth’s gravitational field, it acts as a stationary object. Hence, it also has potential energy. When it revolves around the Earth, there is still potential energy in it which sometimes has to be calculated for a better understanding of its functioning. Since the distance is huge, we need to keep in mind to use well-descriptive methods to avoid any mistakes or confusion.

How to Calculate the Potential Energy of a Satellite?

The potential energy present in the body of the satellite can be calculated by the given formula, i.e., potential energy= -GmM/R

where G = universal gravitational constant ( 6.67408×10–¹¹ m³ /kg/s²)

M = mass of the earth

m = mass of the satellite

R = radius of the earth + the distance of satellite from the earth’s surface

Taking the potential energy of a satellite examples, the mass of a satellite is given to be 1000 kg, mass of the earth = 5.28×10²⁴ kg, and the distance between the satellite and the centre of the earth as 6878000 km.

Then, the potential energy can be calculated as

= -6.67×10–¹¹ ×1000× 5.28×10²⁴ / 6878000

= -5.80×1010 j.

Conclusion

From the above steps, we are now able to calculate the potential energy of a satellite on the earth’s surface. It is also important to note here that the total energy, i.e. the sum of kinetic energy and the potential energy of the satellite, is written with a negative sign which clarifies that the satellites cannot escape the Earth’s gravity.