6.P.3.1 Illustrate the transfer of heat energy from warmer objects to cooler ones using examples of conduction, radiation and convection and the effects that may result.

6.P.3.3 Explain the suitability of materials for use in technological design based on a response to heat (to include conduction, expansion, and contraction) and electrical energy (conductors and insulators).

Energy is the power to change things.

Energy is the ability to do work.

The sun gives out light and heat energy.

Lights use electrical energy.

Batteries for flashlights use chemical energy.

2 Kinds of Energy

One is doing work and the other is waiting to do work.

Kinetic and Potential Energy

Potential EnergyEnergy that is waiting to do work

may be:• Sitting above ground level• Is compressed or expanded in some way• Found in the attraction between atoms

This is potential energy.

Potential Energy is stored energy which means it has the ability to do work Examples:

-A rubber band when you stretch it-A yo-yo before you let it fall

Kinetic Energy

When we see energy doing work, it is pushing or pulling, glowing, or changing temperature.

This is kinetic energy.

Kinetic Energy is energy of motion Examples:

-A rubber band flying through the air-A yo-yo in motion

Forms of Energy

Mechanical energyThermal energyChemical energyElectrical energy

Light energySound energy

Nuclear energy

Mechanical Energy• Energy associated with the motion or

position of an object.• Examples:

– A hammer uses mechanical energy to do work. The mechanical energy of the hammer gives it the ability to apply the force to the nail in order to move the nail.

Thermal Energy• Total energy of the particles in a

substance or material.• When the thermal energy of an

object increases, particles move faster, making the temperature of the object rise.

• Example:– Ice cream melts when its thermal

energy increases

Chemical Energy

• Potential energy stored in chemical bonds.

• Examples:– Food that you eat– Match used to light a candle– Cells of your body

Electrical Energy

• Moving electrical charges produce electricity.

• Examples:– Radios– Lights– Computers– Static shock

Electromagnetic Energy

• Energy that travels in waves.• Examples:

– Visible light– Ultraviolet radiation– Microwaves

Nuclear Energy

• Energy stored in the nucleus of an atom and is released during nuclear reactions.

• Examples:– Sun– Stars– Nuclear Power plant

What kinds of energy can you identify?

Potential Energy Converted to Kinetic

Energy…

When stored energy begins to move, the object now transfers from potential energy into kinetic energy.

Standing still Running

Stored potential chemical energy in a flashlight’s batteries becomes light energy when the flashlight is turned on.

Food is stored energy. It is stored as a chemical with potential energy. When your body uses that stored energy to do work, it becomes kinetic energy.

When you talk on the phone, your voice is converted into electrical energy, which passes over wires. The phone on the other end changes the electrical energy into sound energy through the speaker.

A television changes electrical energy into light and sound energy.

Let’s Review• If you are holding a coin in your

hand, what type of energy does it have?

• If you drop the coin into a piggy bank, what happens to the energy?

Potential, because it has the ability to do work.

It is transferred from potential to kinetic. Dropping the coin changes the stored energy into motion.

A Power Plant

The energy transformation process is carried out in three stages:

• Chemical energy in the fuel (gas or oil) is released as heat in the boiler when it burns with air.

• Heat converts water in boiler tubes to steam, which is then used to drive a turbine that converts energy into mechanical energy.

• Mechanical energy drives an alternator to produce electrical energy.

Law of Conservation of Energy

When energy changes form – the total energy before and after is the same.

When you turn on a car, the chemical energy in the gas is converted to mechanical energy in the engine and heat energy – but all energy can be accounted for.

Temperature• Measure of the average kinetic

energy of the individual particles in an object.

The particles of hot cocoa move faster than those of

chocolate milk.

Which drink has particles with the greater average

kinetic energy?

Hot cocoa

Heat• Movement of thermal energy from a

substance at a higher temperature to another at a lower temperature.

• Heat is thermal energy moving from a warmer object to a cooler object.

How Is Heat Transferred?

• Heat is transferred by conduction, convection, and radiation.

Conduction• Heat is transferred from one particle of

matter to another without the movement of matter itself.

• Example:– Think of a metal spoon in a pot on the stove.

Fast particles of hot electric coil collide with slow particles of cool pot. Particles of pot collide with particles of water, which collide with particles of spoon. As the particles move faster, the metal spoon becomes hotter.

Convection

• Heat is transferred by the movement of currents within a fluid (a liquid or gas).

• Example:– When water at the bottom of a pot is

heated, particles move faster, and farther apart. Heated water is less dense so it rises to the top of the pot. The surrounding cooler water flows into the bottom of the pot in a circular motion called convection current.

Radiation

• Transfer of energy by electromagnetic waves.

• Radiation does not require matter to transfer thermal energy.

• Example:– You can feel radiation from a bonfire or

heat lamp from a distance.

Questions

_____________ energy is stored energy which means it has the ability to do work.

A. Chemical

B. Mechanical

C. Kinetic

D. Potential

Energy is the ability to do __________.

A. nothing

B. work

C. everything

D. none of the above

______________ energy associated with the motion or position of an object.

A. Chemical

B. Mechanical

C. Kinetic

D. Potential