EnergyBy Aditi Atmasidha

Energy is defined as the ability or the capacity to do work.

Wind energy is acting on the windmills in the picture below .

http://www.youtube.com/watch?v=o_5oYuDY2qM

What is Energy?

There are two main types of energy :1. Potential energy also known as stored energy.

2. Kinetic energy also known as motion energy. The first picture is of potential energy & the

second of kinetic energy in action.

Types of Energy

Differences between the two energies

Potential Energy

The energy possessed by body on account of its position or configuration.

It cannot perform work by itself.

The formula is P.E.=mgh. Ex: stretched bow.

Kinetic Energy

The energy possessed by body on accounts of its motion.

It can perform the work. The formula is K.E=1/2

mv raised to2 . Ex: motion of a car.

Elastic Potential Energy Anything that can act like a spring or a rubber band can have elastic potential energy.

Let's take the rubber band for example. To stretch the rubber band you have to use energy. That energy has now been turned into elastic potential energy. To get that energy back, just let go of the rubber band and its potential energy is converted primarily into kinetic energy.

Springs work the same way, but you can either stretch or compress them. Wind-up watches store potential energy in an internal spring when you wind them and slowly use this energy to power the watch.

[This is also known as the Strain Energy]

Types of potential Energy

Gravitational Potential Energy There is a constant attractive force between the Earth and everything surrounding it, due to gravity.

To lift something off the ground it takes energy, so just by lifting an object, that object now has higher gravitational potential energy.

Gravitational potential energy is typically converted into kinetic energy (an object falling) before it is converted into any other type of energy.

Hydroelectric power is generated this way. As the water falls, it turns a turbine, which pushes electrons around, creating an electric current.

Types of potential Energy

Chemical Potential Energy A chemical bond can be thought of as an attractive force between atoms.

Because of this, atoms and molecules can have chemical potential energy.

Anytime two atoms form a strong covalent or ionic bond or two molecules form a weak van der Waals bond, chemical energy is converted into other forms of energy, usually in the form of heat and light.

The amount of energy in a bond is somewhat counterintuitive - the stronger or more stable the bond, the less chemical energy there is between the bonded atoms.

Types of potential Energy

Mechanical Objects have mechanical energy if they are in motion and

have the ability to do work. Mechanical energy is visible kinetic energy. An object possessing mechanical energy displaces the mass of another object. As mass and velocity increase, so does the force of mechanical energy. Heavier and faster objects will have more kinetic energy than lighter and slower ones. Examples of mechanical energy include a wrecking ball hitting a building and large turbines turning because of a blowing wind. Mechanical energy is sometimes referred to as translational energy.

Types of kinetic Energy

Electrical Energy of this type is the movement of positive or

negative electrical charges. The release of the charge changes electrical currents in a light bulb, for example, from potential energy into kinetic energy. This type of energy comes from a variety of sources, such as static, electromagnetic fields and natural phenomena such as lightning. Direct current that flows in a single direction, such as what is found in a battery cell, is another type. Current is a transition of electrical charge.

Types of kinetic Energy

Thermal Particles within a substance that are always moving,

stretching and rotating have thermal energy, which produces heat. Thermal energy is produced by inelastic collisions, meaning that the objects that collide change shape and sometimes stick together. An auto collision is an example of an inelastic collision. Increasing thermal energy in a substance can turn that substance to liquid. Adding more thermal energy can turn the liquid into a gas.

Types of kinetic Energy

Sound/Vibrational Energy Music, whether played live or on a radio or other

source, is a prime example of vibrational or sound energy. Vibrations pass through the air, causing human eardrums to vibrate. The brain interprets the vibrations as sound, but they are, in truth, energy. Cell phones vibrate and move during an incoming call, producing vibrational energy.

Types of kinetic Energy

A source of light makes light. The Sun and other stars, fires, torches and lamps all make their own light and so are examples of sources of light.

When a television is turned on, it produces light. Remember! You must never look directly at the

Sun. It is so bright that it can damage your eyes very quickly.

Some animals, such as fireflies and glow-worms, are light sources. They make their own light to attract mates.

Types of kinetic Energy

Infrared radiation and microwaves can be used to cook food. Microwaves are also used to transmit information - for example, in mobile phone networks.

The electromagnetic spectrum Visible light is just one type of electromagnetic

radiation. There are many other types of electromagnetic radiation with both longer and shorter wavelengths than visible light.

Types of kinetic Energy

frequency type of electromagnetic radiation

wavelength

highest gamma radiation shortest

  x-rays  

  ultraviolet radiation  

  visible light  

  infrared radiation  

  microwaves  

lowest radio waves longest

Types of kinetic Energy

Electromagnetic Spectrum

Electromagnetic Spectrum

Fuel is any material that is capable of releasing energy when its chemical or physical structure is altered. Fuel releases its energy either through chemical means, such as burning, or nuclear means, such as nuclear fission or nuclear fusion. 

Examples of fuels are: Wood, coal, diesel, petrol, natural gas & wax.

What are fuels?

Fuel Consumption in USA

A natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.

This is a image of coal.

What are fossil fuels?

https://sites.google.com/site/environmentforkids/how-coal-is-formed

How is Coal formed?

http://www.hk-phy.org/energy/power/source_phy/flash/formation_e.html

How is Natural Gas & Petroleum formed?

Thank you