Final answer:
Energy is the capacity to perform work, existing in different forms and conserved in amount across the universe. According to the law of conservation of energy, energy cannot be created or destroyed but only changed in form. The source of the universe's energy can be traced back to the Big Bang.
Step-by-step explanation:
What Is Energy?
Energy is a fundamental concept in physics, representing the ability to do work and cause change. It can take various forms, such as kinetic energy, potential energy, thermal energy, and many more. Energy plays an essential role in both everyday events and scientific phenomena. Noteworthy to mention, energy contributes to the energetic personalities we encounter to the sunlight warming us on a beach.
Conservation of Energy
The law of conservation of energy states that the total amount of energy in the universe remains constant - energy can be neither created nor destroyed, only transformed from one form to another. This concept also referred to as energy conservation, implies that the energy present in the universe today has been here since its inception and is simply transforming states.
Origin of Universe's Energy
The question of where the energy in the universe originally came from is tied to cosmology and the Big Bang theory. The Big Bang theory posits that the universe began as a singular point of infinite density and temperature, which expanded and cooled, resulting in the manifestation of matter and energy. The energy within the universe, according to this theory, was created during this event and has since been transformed.
Energy Transformation and Entropy
While energy can transform, as entropy increases, the amount of energy available to do work decreases. We harness energy in various ways on Earth, including fossil fuels, nuclear power, wind energy, geothermal energy, and tidal energy, but as we use these resources, the fraction of the energy that can be converted into work diminishes. In a far future scenario, known as the heat death of the universe, all energy gradients will dissipate, and no work will be possible due to equalized temperatures.