4 Energy – Part B “Energy Transfers”

Syllabus Aims Year 9….

4.2 describe energy transfers involving energy stores:

energy stores:
chemical
kinetic
gravitational
elastic, thermal
magnetic
electrostatic
nuclear

energy transfers:

mechanically
electrically
by heating
by radiation (light and sound)

4.3 use the principle of conservation of energy

4.4 know and use the relationship:

efficiency = (useful energy output/total energy input) x 100%

4.5 describe a variety of everyday and scientific devices and situations, explaining transfer of the input energy in terms of the above relationship, including their representation by Sankey diagrams.

Resources Part I…

Use this PowerPoints for lessons…4B Energy Transfers Part 1

Useful Videos Part 1…

GCSE Physics - Energy Stores, Transferring Energy & Work Done

⭐Test yourself with our quiz: https://cognitoedu.link/physics_energy_stores

In this video you'll learn:
- The 'conservation of energy principle'
- The different energy stores
- How energy is transferred between stores
- What we mean by ...'work done'

General info:
- Suitable for all GCSE and IGCSE courses

Exam board specific info:
AQA - Everything is relevant to your course!
IGCSE Edexcel - Everything is relevant to your course!
Edexcel - Everything is relevant to your course!
OCR 21st Century - Everything is relevant to your course!
OCR Gateway - Everything is relevant to your course!Show More

GCSE Physics - Energy Stores, Transferring Energy & Work Done

Model Steam Engine

Resistance heating with SMEG cooking element

Q2 4B Energy Trans 1C Force and Motion Hooks June 2018 iGCSE Physics

Sankey Diagrams - p159 (Foundation p160)

GCSE Physics - Efficiency

Q12 4B 4D Energy 5B Pressure June 2018 iGCSE Physics

Syllabus Aims Year 10…

4.6 Describe how thermal energy transfer may take place by conduction, convection and Radiation

4.7 Explain the role of convection in everyday phenomena

4.8 Explain how emission and absorption of radiation are related to surface and

Temperature

4.9 Practical: investigate thermal energy transfer by conduction, convection and radiation

4.10 Explain ways of reducing unwanted energy transfer, such as insulation

Resources Part II…

Use this PowerPoints for lessons…. 4B Energy Transfers Part 2

Useful Videos Part 2…

FLIR Silver Blanket Thermal Insulation Infrared IR Reflection

Simple video to show how silver reflects IR

Foil insulation is good, especially for reflecting radiant heat, saving space, and being easy to install, making it great for roofs and walls ...where space is limited, but its overall performance depends heavily on proper installation with air gaps to block all heat transfer (radiation, convection, conduction) and needs vapor barriers in damp conditions, as its R-value is often lower than traditional insulation for its thickness.

Foil insulation, or multifoil insulation, is a high-performance, thin reflective material made of aluminum and wadding, ideal for reducing heat loss and condensation in roofs, walls, and floors. It works by reflecting up to 95% of radiant heat, keeping homes warmer in winter and cooler in summer. It is easy to install, space-efficient for retrofits, and can save on energy bills.

Key Benefits of Foil Insulation

Reflective & Thermal Barrier: Reflects radiant heat while the wadding minimizes conduction and convection, offering a 3-in-1 solution (thermal, vapor, and radiant barrier).

Space Saving: Ideal for tight areas, lofts, and renovations where thicker, traditional insulation is not suitable.

Energy Efficiency: Reduces energy bills by improving thermal efficiency and can be used to meet stringent U-values, particularly in loft conversions.

Easy Installation: Lightweight and flexible, often installed with staples and adhesive tape, making it a
viable DIY project.

Versatile Application: Suitable for roofs, walls, and floors in new builds and renovations.

Types and Uses
Multifoil Insulation Rolls: Flexible, multi-layered, and effective for rafters, timber studs, and, when combined with other insulation, for higher thermal performance.

Foil-Backed Boards: Rigid panels offering high thermal resistance for walls and roofs.
Radiator Foil: Placed behind radiators to reflect heat back into the room.

Crucial Installation Tips
Air Gaps Required: For the reflective properties to work, it is essential to maintain an air gap on one or both sides of the insulation.

Airtight Sealing: Ensure all overlaps are sealed with specialized tape to prevent moisture buildup and air leakage.Show More

FLIR Silver Blanket Thermal Insulation Infrared IR Reflection

Convection Currents Smokin Chimney FLIR 2023

FLIR Camera Conductor or Insulator?

FLIR Light Bulb Efficiency Comparisons - AQA A Level Physics

Hot Hand Print - Thermal Imaging FLIR

Bunsen Flame v Match - Thermal Imaging FLIR

Light Bulb v CFL Energy Efficiency in Infra Red - Thermal Imaging FLIR

Liquids Conduct Heat Poorly

Infrared Radiation

Conduction in a Copper Rod

Convection in a Mineshaft or Chimney Air Density

IR Radiation and Matt black or Silver Absorption

Beyond the red end of the visible range, but at frequencies higher than those of radar waves and microwaves, is the infrared region of the electromagnetic spectrum. William Herschel, a ...German-born British musician and self-taught astronomer, discovered this form of radiation in 1800 by exploring, with the aid of a thermometer, sunlight dispersed into its colors by a glass prism.

Infrared radiation is absorbed and emitted by the rotations and vibrations of chemically bonded atoms or groups of atoms and thus by many kinds of materials. For instance, window glass that is transparent to visible light absorbs infrared radiation by the vibration of its constituent atoms. Infrared radiation is strongly absorbed by water and by the atmosphere. Although invisible to the eye, infrared radiation can be detected as warmth by the skin. Nearly 50 percent of the Sun's radiant energy is emitted in the infrared region of the electromagnetic spectrum, with the rest primarily in the visible region.

Infrared radiation plays an important role in heat transfer and is integral to the greenhouse effect, influencing the thermal radiation budget of the Earth on a global scale and affecting nearly all biospheric activity. Virtually every object at the Earth's surface emits electromagnetic radiation primarily in the infrared region of the spectrum.

In this video we prove the simple idea that a black object can absorb IR strongly whilst a silver metallic object does not. This is a simple test for use at KS3 to help differentiate between materials. We can liken it to putting your hand on a white painted line on a black tarmac road and seeing that the black tarmac is hotter. Also a white shirt is reflective and a black shirt absorbs more IR in hotter climates.

Dark, matt surfaces are good absorbers and emitters of infrared radiation.

Light, shiny surfaces are poor absorbers and emitters of infrared radiation. An example of this is the silvering inside a vacuum flask.

Uses of infrared radiation.

infrared heaters give out infrared radiation to heat a room

PIR’s (passive infra red devices), these can be found as part of home security alarm systems

thermal imaging cameras, police helicopters use these cameras to help find people when flying at night

the silvering on the inside of a vacuum flask helps prevent heat loss from coffee in the flaskShow More

Led replacement bulbs

These are cool new led bulbs which are energy efficient.

Advantages of LED Bulbs

The operational life of a LED lamp (up to 50,000 hours) is in contrast to the average life ...of an incandescent bulb, which is approximately 1000-2000 hours. For lights in very inaccessible places, using LEDs would eliminate the need for difficult bulb replacement for many years. It really is simply a case of fit-and-forget!

The cost of LED lights compared to traditional incandescent bulbs

The main advantage of LED lighting is clearly in the energy savings (and therefore money savings!) which are achieved. The way in which LEDs achieve this energy saving is by the amount of heat they create. Traditional incandescent bulbs lose up to 90% of their power on creating heat which is wasted. LEDs save on power consumption by generating considerably less wasteful heat.

The cost savings are considerably higher than just the energy saving if you consider the cost of 30-50 replacement incandescent bulbs. With LEDs, there would be no replacement bulbs required for many years and they often pay for themselves in energy savings in less than a year of use.

For commercial premises like retail outlets, hotels and offices, there is a significant maintenance cost in replacing light bulbs which can be virtually eliminated. This is an important point, especially where there are a large number of bulbs in place. Eliminating the constant need to replace bulbs by changing to LED options can be very attractive, and after the cost of replacing halogen bulbs is taken into account, LED bulbs really are the ultimate energy saving bulb.

Compact Size

As the LEDs which provide the light in the bulbs are so small, the high powered LED bulbs are direct replacements for halogen bulbs in terms of size. This gives LEDs a distinct advantage over energy saving CFL bulbs which are generally larger than their halogen counterparts, and can look unsightly in some elegant light fittings.

When it comes to display or accent lighting, the compact size of LED light bulbs, as well as the availability of coloured lighting provides for very versatile lighting which is appropriate everywhere from retail displays to Christmas lights in homes.

Practical Advantages

LED light bulbs represent the safest form of lighting and even when they go wrong, they are still not dangerous to be around, unlike incandescent bulbs which generate lots of heat when in use and have even been known to explode when things go wrong. LEDs are not strictly light bulbs, they are an electrical circuit (semiconductor). They do not contain filaments and therefore are not prone to the usual light bulb problems associated with incandescent bulbs.

LEDs will invariably last 30 to 50 times longer than standard incandescent bulbs, whilst using an average of 90% less power which makes them ideal for places where lights are switched on for lengthy periods of time. More durable with no fragile parts, the bulbs generate virtually no heat and are therefore safe in almost all areas around the home. The cool running temperature of LEDs could reduce air conditioning costs, and the fire risk associated with overheating incandescent bulbs is not an issue with LEDs.

As LEDs are very strong and durable, they are able to endure vibration so they are appropriate for use in many places where existing bulbs are subject to regular failure, eg around heavy machinery. They are also able to tolerate low temperatures and therefore allow more flexibility in their use.

LEDs do not produce any UV (ultraviolet) or IR (infra red) radiation, and can thus be used to light paintings or other precious artefacts without causing any fading. Unlike CFL or fluorescent lighting, LED lighting also does not flicker, and this reduces eye strain and other problems associated with flickering lighting solutions.

Taking Care of the Environment

Taking care of the environment has become a way of life in the 21st century, and we all have a duty to try and reduce our carbon footprints, be it at home or in our businesses. An easy way to make a start in improving the efficiency of our homes and businesses is through LED lighting. Environmental specialists list improving energy efficiency as an important factor to reduce our impact on the environment. LED lights use up to 90% less electricity than standard halogen bulbs and have an extremely long lifespan which equates to considerably reduced carbon emissions and less waste because fewer lamps need to be disposed of.

Have you seen the light yet?Show More