ENERGY – PART 2 1 – WHAT IS ENERGY? 2 – FORMS OF ENERGY 3 – ENERGY TRANSFORMATION 4 – ENERGY TRANSFER

WHAT IS ENERGY? INTERNATIONAL SYSTEM OF UNITS – 1 (joule) represents the energy needed to lift an object weighing 1 (newton) to a height of 1 (meter) 1 N = 100 g 1 M = 100 cm 1 J = 100g x 100cm 1J = 1N x 1M

WHAT IS ENERGY? Energy is the capacity to do work or effect a change. In the international system of units, energy is expressed in joules. Pg. 34 Textbook

FORMS OF ENERGY ENERGY FORM ENERGY SOURCE SOLAR ENERGY SUN ELASTIC ENERGY WIRE SPRING ELECTRICAL ENERGY POWER STATION THERMAL ENERGY FIRE RADIANT ENERGY ELECTRIC LIGHT BULB CHEMICAL ENERGY LIVING CELL MECHANICAL ENERGY MOVING VEHICLE WIND ENERGY WIND SOUND ENERGY SOUND HYDRAULIC ENERGY WATERFALL / CURRENT NUCLEAR ENERGY NUCLEUS OF AN ATOM KINETIC ENERGY POTENTIAL ENERGY

FORMS OF ENERGY Thermal Energy Thermal energy: is the energy that comes from the random motion of particles that make up a substance. The higher the temperature of a substance, the more energy it contains because there is greater movement of its particles. Warm Cold Pg. 36 Textbook

FORMS OF ENERGY Radiant energy Radiant Energy: is the kind of energy contained in and transported by electromagnetic waves. The quantity of energy depends on the wavelength :the shorter the wavelength, the more energy the wave can transport. The quantity of energy also depends on the quantity of energy emitted by the source : the more radiation emitted, the greater the energy emitted as well. Shorter wavelength = Greater its energy Pg. 37 Textbook

FORMS OF ENERGY Chemical Energy Chemical Energy: is contained in the bonds of a molecule. It is energy in reverse, since the bonds need to be broken to free the energy they contain. The amount of energy depends on the strength of the bonds between the atoms. The stronger the bond the more energy it contains. Pg. 38 Textbook

FORMS OF ENERGY Mechanical Energy Mechanical energy: is the energy that results from the forces acting on an object. It depends on the objects speed, its mass and its relationship to its surroundings. Pg. 39 Textbook

& Energy Transformation Energy Transfer & Energy Transformation GOING FROM ONE SOURCE TO THE NEXT CHANGING FROM ONE SOURCE TO ANOTHER

ENERGY TRANSFER A movement of energy from one place to another while maintaining it’s form Ex. Mechanical energy of a car’s motor is transferred to mechanical energy to the car’s tires to move the car.

Energy Transfer Energy transfer is the movement of energy from one place to another. For example; from the sun to the leaves on a tree. Most of the time, energy transformation and transfer occur at the same time. Pg. 41 Textbook

ENERGY TRANSFORMATION Changing energy from one form of energy to another form of energy Ex. A Burning log – molecules of log transform into radiant energy (light) & thermal energy (heat)

Energy transformation and transfer The transformation of energy is the changing of energy from one form to another; for example from chemical energy to mechanical energy. Pg. 41 Textbook

Energy Transformation & Energy Transfer Energy transformation and transfer help to carry out different kinds of change ; for example, physical changes and chemical changes.

HEAT HEAT – The transfer of thermal energy from one place to another. Heat will always travel from the hotter place towards the colder place

KINETIC vs. POTENTIAL ENERGY Kinetic Energy is the energy that an object possesses because of its motion. Potential Energy is the energy that an object possesses because of its position and/or mass and/or arrangement of particles in its system