سلاسل الطاقة: النشاط 9

• Activity 9: Building Energy Chains
• After learning how to trace the path of energy in devices, we can now draw a series of energy pictures and their transformations for any device.
• The model should illustrate the paths of energy transfer, starting from the inputs to the outputs.

Completing the Energy Image Series for Operating a Vacuum Cleaner

• Inputs (Incoming Energy):
• Energy (1): Enters the vacuum cleaner through a copper wire.
• Outputs (Resulting Energy):
• Energy (2): Occurs during air movement and picking up dust and things.
• Energy (3): Represented in the noise produced when operating the device.
• Energy (4): Felt when touching the device during operation.

The Mobile Phone Example

• Device function: Communication via light, sound, and information processing.
• Inputs:
• Electrical energy enters the device and is stored inside the battery shown in picture 1.
• Energy Storage:
• Incoming energy is stored in the phone in the form of chemical energy inside the phone's battery shown in picture 2.
• Outputs shown in picture 3:
• When the device is turned on, some of the stored energy converts into other forms of energy, including:
  • Useful energy:
  • Light energy: illuminates the phone Screen.
  • Sound energy: to hear the phone's sound.
  • Wasted energy:
  • Heat energy: causes the device's temperature to rise, but does not perform a function.

Completing the Diagram Showing the Path of Energy When Operating the TV

• Incoming Energy:
• Energy (1): Enters the device via a copper wire.
• Resulting Energy:
• Energy (2): We hear it when the device emits sounds.
• Energy (3): We see it when the Screen lights up.
• Energy (4): We feel it when touching the device during operation.
• Lesson Four
• Activity 8: Tracing the Energy Path
• Placing a Check Mark (✓) or an X Mark (✗) for the Following Statements:
• The resulting sound energy when operating an electric mixer is beneficial energy: False.
• Part of the energy is lost when it transforms from one form to another: False.
• In the previous activity, we learned that energy is neither created nor destroyed from nothing. This means that the energy that enters any device must completely exit it in the end, either in the same form or in another form.

Example 1: Hair Dryer

• Device function: Drying hair using hot air (thermal energy).
• Inputs (Incoming Energy):
• Electrical energy: Enters the device via a copper wire.
• Outputs (Resulting Energy):
  • Useful energy (helps the device perform its function):
  • Thermal energy: Heats the air.
  • Kinetic energy: Pushes the hot air.
  • Wasted energy (not used):
  • Sound energy: Causes noise and does not help the device perform its function.
• Important Note:
• It may seem that the device loses some energy, but in reality, this part is not destroyed, but rather transformed into another form that does not help in achieving the intended function of the device.

Example 2: Riding a Bike

• Cycling:
  • When you eat breakfast, your body gets chemical energy present in the food.
  • When you push the bike pedals with your foot, the chemical energy in your body converts into kinetic energy, causing the bike to move.
  • When the bike tires rub against the ground surface, the kinetic energy converts into thermal energy as a result of friction.

Example 3: Energy Transformations When Lighting an Electric Bulb

• When operating a bulb, electrical energy converts into light energy, which illuminates the room.
• Part of the electrical energy converts into thermal energy that you can feel if you put your hand near the bulb when it's been on for a while.
• Conclusion:
• Energy neither vanishes nor is created from nothing, but it transforms from one form to another.

Additional Information:

• Energy may change from one form to another, but it never vanishes.

Lesson Three:

• Activity 6: Energy and Devices We Use in Our Daily Lives
• We will learn the energy used (input) and the energy produced (output) in some devices.
• Some of the energy entering the device leaks out in the form of other unused forms and is considered wasted or lost energy.

Electric Lamp Example

• Used energy (input): Electrical energy, shown in the electric light bulb illustration.
• Resulting energy (output): light energy, is useful. Thermal energy, which is considered wasted.
• Device function: Lighting
• Complete the Following Table to Identify the Function of Each Device, the Energy Used to Operate It, and the Forms of Energy Produced:
  • Handheld lamp:
  • Function: Lighting
  • Used Energy: Chemical
  • Resulting Energy: Light - Thermal
  • Guitar:
  • Function: Producing musical tunes when played
  • Used Energy: Movement energy
  • Resulting Energy (1) : Sound
  • Wristwatch Operating on Battery:
  • Function: Knowing the time
  • Used Energy: Chemical energy
  • Resulting Energy (2): Movement of hands etc
  • Electric Oven:
  • Function: Heating and cooking food
  • Used Energy: Electrical energy
  • Resulting Energy: Thermal - Light
  • Toy car operating on Spring:
  • Function: Playing and amusement
  • Used Energy: Potential energy
  • Resulting Energy (3): Movement
  • Manual Bell:
  • Function: Alerting via issuing sound
  • Used Energy: Movement energy
  • Resulting Energy: Sound energy
• Important Note:
• Some energy inputs may be wasted in other forms, such as some of the kinetic energy used to operate a pencil sharpener coming out in the form of heat from friction.
• Most of the lost energy leaks out in the form of thermal energy.

Example 1: Heating a Pot of Water on Fire

• The light energy coming from the sun helps in the growth of trees, and energy is stored inside the trees in the form of chemical energy.
• When burning tree wood, thermal energy is produced which works to heat the water in the pot.

Example 2: Operating a Hair Dryer

• The trees get light energy coming from the sun.
• Coal consists of remnants of huge trees that were buried far from the Earth's surface millions of years ago and store chemical energy.
• At Coal burning, the stored chemical energy inside it, is converted into thermal energy.
• At power generation stations, thermal energy converts into kinetic energy resulting in electrical energy which reaches homes via electric wires made of copper.
• The hair dryer converts electrical energy into thermal energy in addition to sound energy and kinetic energy.

Lesson Three:

• Activity 5: The Chain Photos of Energy
• Most images of energy we use come from the sun.
• To identify the transformations of energy from the sun to the different devices, we can draw a diagram that clarifies these transformations and is known as the Chain Photos of Energy.
• Chains of Energy Images: A figure or diagram that displays the energy path and its transformations from the sun to the different devices.

Examples of Series Images of Energy

• Example 1: The Eating Process. - The following diagram illustrates a chain of energy images when eating (an orange):
• Plant tree absorbs the light energy and transforms it to a chemical energy stored in a form of sugared materials
• The energy produced from the sun and it reaches ground in a form of light and thermal energy shown in picture 1.
• When you eat the orange, your body uses the chemical energy stored in the food and changes it to kinetic energy to do the different activities shown in picture 3.

Power Inside Devices

• Many devices and toys can be operated, such as remote-controlled cars, trucks, and airplanes.
• These devices and games need energy to move and do their work, such as rotating, moving arms, or operating cameras.
• Most of these games use batteries that store chemical energy.

Device Operation Using Batteries

• The chemical energy stored in the battery converts into electrical energy when starting the device, as shown in picture 1.
• Electrical energy flows from one side (pole) of the battery to the other, as shown in picture 2.
• Electrical energy in the toy converts into other forms of energy such as kinetic energy and sound energy, images 3 and 4.
• When the battery runs out, it can be recharged again by connecting it to the charger or replacing it with a new one.

Device Battery Types

• Renewable Energy (Solar)
• Used by some cell phones, shown in solar cell illustration.
• Electricity: shown in appliances and microwave illustrations.
• Used by some devices such as:
• Electric ovens
• Television
• Gas: shown in oven illustration.
• Used by some of the devices
  • Gas heaters
  • Gas ovens