“I hope I have helped to raise the profile of science and to show that physics is not a mystery but can be understood by ordinary people.” -Stephen Hawking
Physics is known as the knowledge of nature and is the natural science that studies matter, motion and its behaviour through space and time. While studying physics, pupils learn more about energy and force.
Some may think that physics is too difficult of a subject to grasp due to its equations and inspecting of scientific topics. Nevertheless, this is not the case due to the fact that it is a scientific discipline that can be studied by all interested ones no matter what their previous expertise was.
In the United Kingdom, physics and its various sub-topics such as energy can be studied as a GCSE subject when students are in their last years of secondary school.
Superprof will now examine the GCSE Physics Syllabus’ first topic of Energy in order to help potential students decide if this syllabus is for them. Since there are various examination boards across the United Kingdom offering GCSE qualifications, we will closely review the GCSE Physics Syllabus that is offered by the Assessment and Qualifications Alliance (AQA) in a series of articles.
Magnetic energy is stored when repelling poles have been pushed closer together. (Source: pixabay)
The GCSE Physics option is part of Single Science and is divided into eight different topics. The first of the eight topics is Energy. Like all of the topics in this section, it is divided into different sections of learning. The first of the five main sections in the Energy topic of the GCSE Physics option provided by the AQA is Changes in Energy Stores.
Energy can be described as being separated into different “stores.” It cannot be destroyed or created but transferred or stored in distinct ways.
The seven main stores of energy are furthered examined in this section and be described as the following:
Energy can remain in the same store for hundreds or even millions of years or sometimes only for a slight period of time such as a second or fraction of a second. These are known as energy transfers and they can be observed all the time.
Energy can be transferred in one of four energy transfers known as:
The word “work” is used as a scientific way of saying that energy has been transferred.
Energy flow diagrams have been created to show how energy has been transferred from one store to another. The most commonly utilized diagrams are the transfer diagrams and the Sankey diagrams.
In this first section in the Energy topic of the GCSE Physics syllabus, students are also taught about energy dissipation which is a scientific term used to describe ways in which energy is wasted and not fully utilized. Energy is usually lost by heating up the surroundings or is dissipated as sound waves.
Energy can also be conserved and there are various examples that students analyze to understand this concept of physics.
Students also learn the calculations of kinetic energy using an important equation. Exercises are undergone to test understanding of this physical equation.
Energy is an extremely crucial part of physics due to the fact that it allows work to be done. The rate at which energy is transferred is called power and the amount of energy that is transferred is known as efficiency. While students are studying the first topic of Energy they analyze the definitions, examples, and equations in work, power and efficiency.
When a force causes a body to move, work is being done on the object by force. When the work has been completed, the energy has been transferred from one store to the other. It can be described this way: energy transferred= work done.
The work that was done and the energy transferred can both be measured in joules (J).
Calculating work done depends on two things: the size of the force acting on the object and the distance through which the force causes the body to move. The equation is the following, work done= force x distance or W= F x d.
The work done is measured in joules (J), force is measured in newtons (N) and distance (d) is in the same direction of the force and is measured in metres (m).
Students next analyze the equation of power. The more powerful a device the more energy it will transfer per second. Calculating power can be done using a simple formula that is not too difficult to grasp:
(Images are courtesy of BBC.com/bitesize/guides)
Power is measured in watts (W), work done (W) is measured in Joules (J), and time (t) is measured in seconds (s).
One watt is equal to one joule per second (J/s). This brings students to the conclusion that for every extra joule that is transferred per second, the power is increased by one watt.
Devices such as televisions, refrigerators and washing machines are designed to waste as little energy as possible. As much energy input as possible should be transferred into useful energy stores. Efficiency is defined by determining how good a device is at transferring energy input to useful energy output.
An efficient device wastes very little energy and an inefficient device wastes a lot of energy.
Students in this section learn equations to determine efficiency as a decimal or percentage. The equations are as follows:
(The images above are courtesy of BBC.com/bitesizes/guides.)
Examples and questions of efficiency and power are analyzed in the GCSE subject of Physics.
In this third section of the topic of Energy, students examine different concepts and perform various experiments. First and foremost pupils learn the basics of how energy is transmitted by conduction, convection or radiation. The conductivity of different materials can be determined by comparing the time taken to transmit energy through them.
Conductors are materials that allow internal or thermal energy to be transferred through it relatively easy. All metals are very good conductors.
Insulators are materials that will not allow the easy flow of energy through it. A cushion on a dining room chair would be an insulator since energy or heat will not transfer through it rapidly.
Bunsen burners can be used to used in scientific experiments to determine thermal conductivity. (Source: pixabay)
This a measure to determine how well a material conducts energy when heated. There are many experiments that can be done to discover this using a Bunsen burner. Rods made of different materials can be heated and the one that heats the quickest is said to have a high thermal conductivity.
The thermal conductivity is watts per metre per degree Celsius (W/m/°C). For example, copper has a thermal conductivity of 385, glass has one of 0.17 and brick has one of 0.15.
Students need to complete some required practical investigations during this section of Energy.
Pupils investigate different methods of insulation and remember the importance of recording and making correct measurements of time and temperature, observe the effect of different materials as thermal insulators and use appropriate scientifical objects to measure the effectiveness of different materials.
Heating materials, the heating capacities of different objects and calculating thermal energy changes are all analyzed in this section to further understand the topic of Energy.
Energy from the sun or solar power is a renewable energy that is commonly used today. (Source: pixabay)
All humans, animals and man-made devices transfer energy. The energy transferred is mostly supplied by electricity which was generated from other energy sources. There are both renewable and non-renewable sources of energy.
Almost everything needs energy and there are various resources of energy available on planet earth. Some of these energy resources include fossil fuels, nuclear fuel, bio-fuel, wind, hydroelectricity and geothermal just to name a few.
Energy is needed in a variety of places for many different things such as the following:
Students analyze where most energy resources are needed, how some can cause damage to the environment and the patterns and trends of energy consumption.
The definition and examples of renewable and non-renewable energy resources are taught to pupils in this section.
It is important to note that non-renewable energy resources damage the earth more than renewable resources. The following table describes the features of some of the most common renewable energy resources used today:
|Energy Resource||Energy Store||Various Uses||Environmental Impact|
|Geothermal||Thermal||Generation of Electricity and Heating||Very little|
|Hydroelectricity||Gravitational Potential||Generation of Electricity||Local inhabitants and wildlife are affected by large areas that are flooded|
|Sun||Nuclear||Generation of Electricity and Heating||The solar panels are of very little damage to the environment|
|Wind-Power||Kinetic||Generation of Electricity||According to many windmills ruin views and require too much space|
After the first four topics of the GCSE Syllabus are completed, students undergo Paper 1 or the first assessment. It is comprised of a written exam of an hour and 45 minutes, Foundation and Higher Tier, it is graded out of 100 marks and is worth 50% of the GCSE.
The questions are multiple choice, structured, closed short answer and open response.
Here is a slight description of the potential questions found on the examination:
All the information that we have considered in today’s article gives students a heads up of what to expect when studying the first topic of Energy in the GCSE Physics Syllabus offered by the AQA. Preparation is essential to succeed and rise above your classroom competitors.
It would be wise to observe the other topics considered in the GCSE Physics Syllabus such as electricity, particle model of matter, atomic structure, forces, waves, magnetism and electromagnetism and space physics before deciding to study this GCSE subject.