# Energy

Energy is the ability to perform work in physics. It could exist in several different forms, such as potential, kinetic, thermal, electrical, chemical, radioactive, etc. Additionally, there is heat and work, which is energy being transferred from one body to another. Energy is always assigned based on its nature once it has been transmitted. Thus, heat transmitted may manifest as thermal energy while work performed may result in mechanical energy. Motion is a property of all energy types. For example, if a body is moving, it possesses kinetic energy. Even while at rest, a tensioned object like a spring or bow has the ability to move; this is because of its design, which includes potential energy. Similar to kinetic energy, nuclear energy is potential energy since it originates from the arrangement of subatomic particles in an atom's nucleus.

### First Law of Thermodynamics

Energy can only be transformed from one form to another; it cannot be created or destroyed. For instance, the potential energy that a box has from being high up on the slope is transformed into kinetic energy, the energy of motion, as the box slides down a hill. The kinetic energy from the box's motion is transformed into thermal energy, which heats the box and the slope as it comes to a stop due to friction.

Other mechanisms exist for converting energy from one form to another. For instance, numerous types of equipment, such as fuel-burning heat engines, generators, batteries, fuel cells, and magnetohydrodynamic systems, produce usable mechanical or electrical energy.

## Unit of Energy

Energy is quantified in joules according to the International System of Units (SI). A one-newton force acting over a one-metre distance produces one joule of work.

In discussions of energy, numerous types of units are employed. They can be divided into two groups:

(a) those whose definitions are unrelated to a specific fuel, which we refer to as "basic" units; and

(b) those whose definitions are tied to idealised attributes of a particular fuel, which we refer to as "source-based" units.

### Joule (J)

This is the fundamental energy unit of the metric system, or the International System of Units in a later, more thorough version (SI). In the end, the metre, kilogramme, and second are used to characterise it.

### Calorie (cal)

In the past, the definition of a calorie included the heating of water. Consequently, according to a conventional definition, one calorie is the quantity of heat needed to raise the temperature of one gramme of water by one degree Celsius, from 14.5 to 15.5 degrees. The "calorie" measured for other temperature ranges differs slightly from this, which is frequently referred to as the 15 °C calorie. The calorie has more recently been defined in terms of the joule; historically, the calorie and joule have been referred to as the mechanical equivalent of heat.

## How can you use our Online Energy Converter?

1. Enter your energy amount in the box
2. Select unit
3. Click on convert
4. Results appear as shown in figure given below 