Definition of Energy – Energy is needed for daily activities. For example, when we exercise, of course we feel tired. After feeling tired, we naturally rest, starting from sitting, drinking or even consuming food.
All of the above activities require energy. The clock moves every second requiring energy from a device we call a battery. Batteries also have to be replaced over time, as they only have energy for a certain amount of time.
There are many types of energy, ranging from artificial energy to natural energy. Natural energy that can be used by humans is wind, water, oil, light. The greatest light energy today is the sun.
Solar energy also helps plant processes to photosynthesize, make rain and others. One of man-made energy is nuclear energy. But it takes experts to stabilize the radiation produced. Below will be explained more about energy.
Definition of Energy
Energy, in physics, is a unit of capacity to do work or work. There are several forms of energy, kinetic, thermal, electrical, chemical, nuclear, and many other forms of energy. The law of the conservation of energy states that energy can be changed in form, but cannot be created or destroyed.
The unit of measurement in the International System of Units (SI) for energy is the joule, which is the energy transferred to an object by moving it one meter against a force of one newton.
All forms of energy are associated with motion, for example, every object has kinetic energy when it moves. A tensioned device such as an arc or spring, even when at rest, has the potential to create motion.
It also contains potential energy because of its configuration. Similarly, nuclear energy is potential energy because it results from the configuration of the subatomic particles in the atomic nucleus.
Common forms of energy include kinetic energy from a moving object, potential energy stored by an object’s position in a gravitational, electric or magnetic force field, elastic energy stored by stretching a solid object, chemical energy released when fuel burns, radiant energy carried by light, and heat energy due to the temperature of an object.
Mass and energy are closely related. Because of the mass-energy equivalence, any object that has mass when at rest is called rest mass. Rest mass also has an equivalent amount of energy which is called rest energy, and any additional energy of any kind that an object gains on top of that rest energy will increase the object’s total mass just as much as it increases its total energy. For example, after heating an object, the increase in its energy can in principle be measured as a small increase in mass, with a fairly sensitive scale.
As previously discussed, living organisms need energy to stay alive, such as the energy that humans get from food and oxygen. Human civilization needs energy to function, which it gets from energy sources such as fossil fuels, nuclear fuel, or renewable energy.
Earth’s climate and ecosystem processes are driven by the radiant energy the Earth receives from the Sun and the geothermal energy contained within the Earth.
Types of Energy
Types of energy can be categorized into two broad categories, namely kinetic energy or energy of moving objects and potential energy or stored energy. These are the two basic forms of energy. Here are some types of energy namely heat energy, light energy, chemical energy, nuclear energy, electrical energy, motion energy, sound energy, elastic energy and gravitational energy.
1. heat energy
Thermal energy is the energy that comes from a substance whose molecules and atoms vibrate faster due to an increase in temperature. The molecules and atoms that make up matter are in motion all the time.
When a substance is heated, the increase in temperature makes these particles move faster and bump into each other. Thermal energy is energy that comes from a substance that is heated. The hotter a substance, the more its particles move, and the higher its heat energy.
Examples of heat energy that exists in everyday life are the warmth from the sun, a cup of hot cocoa, baking a cake in the oven, and heating the body from a heater. Hot chocolate has heat energy from its vibrating particles.
When you pour cold milk into hot chocolate, some of this energy is transferred from the chocolate to the particles in the milk. Similarly, when you touch a hot object, heat energy is transferred from the object to your skin.
2. chemical energy
Chemical energy is stored in the bonds that link atoms to other atoms and molecules to other molecules. Because chemical energy is stored, chemical energy is included in the form of potential energy.
When a chemical reaction takes place, stored chemical energy is released. Heat is often produced as a by-product of a chemical reaction; this heat generated is called an exothermic reaction.
Chemical energy is the most widely used type of energy in the world, because it is very important for the existence of humans and nature. Here are some examples of chemical energy used for human life, such as the food we eat contains stored chemical energy. When the bonds between atoms in food loosen, chemical reactions occur, and new compounds are created.
The energy generated from these reactions keeps us warm, helps us move, and allows us to grow. Different types of food store different amounts of energy. Dry wood contains stored chemical energy. When burning wood in a fireplace, chemical energy is released and converted into heat energy and light energy.
3. nuclear energy
Nuclear energy comes from the atomic nucleus. Energy released by nuclear fusion fuses together or nuclear fission. Nuclear plants use the nuclear fission of a radioactive element called uranium to generate electricity. Atoms are the particles that make up every object in the universe, consisting of neutrons, protons and electrons. The elements that make up the atom contain a nucleus, from which nuclear energy originates.
Nuclear energy is released from atoms through Nuclear Fusion and Fission. Nuclear fusion, when atomic nuclei are fused or fused together, is how the sun generates energy. Nuclear fission, when the atomic nucleus is split. This is the method used by nuclear plants to generate electricity. The fuel for nuclear energy is uranium.
Uranium is a radioactive element that was formed when the earth was first created. It occurs naturally in certain rock types. Uranium is one of the few elements that easily splits open, so it is used as a fuel by nuclear power plants. Although uranium can be found all over the world, it is still a non-renewable energy source.
4. electrical energy
Electrical energy is a type of kinetic energy caused by moving electric charges. The amount of energy depends on the speed of the charge, the faster the charge is moving, the more electrical energy it carries. Some examples of electrical energy are car batteries, chemical reactions produce electrons that have the energy to move in an electric current. These moving charges provide electrical energy to the circuits inside the car.
During a thunderstorm, lightning is an example of electrical energy, what we can see is electricity in the atmosphere being released. Electric eels also generate electrical energy, which they use to defend against predators and to electrocute their prey. Electric eels can generate up to 600 volts of power, five times the amount of power that a standard wall outlet can provide.
5. light energy
Light energy is a form of electromagnetic radiation of different wavelengths, which is visible to the human eye. Light energy is a type of kinetic energy. Light energy propagates in the form of waves. This energy is so fast in fact that nothing travels faster than the speed of light. The speed of light can go as fast as 300,000 km per second.
Light energy is formed because light is made up of photons, which are like tiny packets of energy. When the atoms of an object heat up, photons are produced from the movement of the atoms. The hotter the object, the more photons it generates. Examples of light energy are stars, lamps or lasers.
6. motion energy
Motion or mechanical energy is energy stored in moving objects. Actual energy of motion is the sum of the kinetic and potential energy in an object that is used to do work. Work is when a force acts on an object and causes it to move, change shape or position, or do something physically. When pushing the door open, ‘work’ has been done on the door, causing it to open.
Also, let’s say you have an iron hammer and you want to use it to drive a nail into a piece of wood on the floor. The iron hammer itself has no kinetic energy, but has some potential energy due to its weight. To do the work of driving a nail into a piece of wood, you must first lift the hammer to increase the hammer’s potential energy. Next, you have to use force to move it downwards at high speed to hit the spikes, so it now has kinetic energy.
7. sound energy
Sound energy is the movement of energy through a substance in waves. Sound energy propagates in the form of waves. Unlike light energy, sound cannot travel through a vacuum, because there are no atoms to transmit vibrations. Sound energy is produced when a force causes an object or substance to vibrate.
The energy is then transferred through the substance in the form of waves, which are called sound waves. Sound can be transmitted by solids, liquids, and gases, because such media have atoms to transmit vibrations. Some examples of sound energy in everyday life are clapping, singing or speaking, playing musical instruments and others.
8. elastic energy
Elastic energy is a form of potential energy, because it is stored in the bonds between atoms in an object or substance when it is under pressure for a while. This pressure can be caused by the object being stretched or pinched. Elastic energy is stored in the bonds between atoms in an object or substance. These bonds absorb energy when stressed, and release energy when relaxed.
Forces acting on an object can cause it to deform temporarily, such as when stretching a rubber band, or pressing a squishy ball with your hands. When this occurs, elastic energy may be stored within the object, ready to be released when the object returns to its original shape. Some examples of elastic energy are springs, sponges and catapults.
9. gravitational energy
Gravity is a force that tries to pull two objects towards each other. Earth’s gravity is what keeps things on the ground and what causes things to fall. Earth has gravity, useful for holding everything close to the planet. Trees, water, animals, buildings and the air we breathe are all held here by gravity.
The planets, their moons and the stars in the universe have gravity. Even our own body has gravity. Earth’s gravity is so much stronger than our own that we don’t notice the gravity that our bodies have. Black Hole or black hole has the highest gravitational pull.
Energy Function
Energy is the main requirement for living things in carrying out activities. Nature produces a lot of energy that can be utilized by humans, such as the sun, sea and others. Energy has many functions for various fields. Starting from the perspective of classical mechanics, several mechanical formulas have been developed using energy. The concept of energy in classical mechanics is generally useful for modern physics.
In biology, energy has a role for biological systems, from the biosphere to the smallest living things. The movement of energy occurs in the biosphere, the layer of the earth where most life exists. Starting from the root system to the deepest trenches in the ocean. Energy has a role in the growth and development of cells of an organism, including humans.
How to save energy
An easy way to save energy is to make small changes to your daily habits and do some basic maintenance routines. Here are some ways to save energy that you can do at home.
- Wash clothes at once: when washing clothes, always try to wash clothes in one batch. Washing machines are designed to be able to wash a lot of clothes. By washing clothes at the same time you can save your electricity and energy.
- Clean electronics: every electronics work more efficiently when they are clean from dust and dirt. If the tool works more efficiently, it does not require a lot of energy.
- Do not open the refrigerator and oven for too long: Always try to close the oven when cooking. Don’t stand in front of the fridge for too long, the longer the fridge is open, the more energy it takes to keep food cold.
- Open the window blinds: Letting sunlight into the house will benefit the room. The room is not damp, there is no need to turn on the lights, moreover, sunlight can warm up a cold room.
- Turn off the lights: Turn off the lights when you’re not in the room. Light bulbs waste 95% of energy and give off heat. Use it sparingly, or replace it with a lamp that uses a sensor so it’s much more economical.
- Don’t take a long shower: Humans do need a shower to clean their bodies, but taking a long shower especially using a shower can consume 2.5 gallons per minute.
- Unplug unused plugs: Charging a cellphone or laptop battery is indeed a primary need. However, if you don’t unplug chargers that are not in use because they will draw power continuously.
- Use sleep or hibernate mode: If you are using a laptop, and leave it in screen saver mode, it’s best to put it in sleep or hibernate mode. That way the electrical energy used becomes more efficient.