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4.1.1 Energy changes in a system, and the ways energy is stored before and after such changes Taught
Practiced
Mastered
Presenting and writing descriptions and explanations:
Ask students to explore questions such as:
Why do the wheels of a bike get very hot when braking hard?
Which type of car is more efficient – petrol or electric?
How is the gravitational potential energy store of an object increased?
Why does a flow of electrons along a wire allow bulbs to light and motors to spin?
Describe the changes involved in the way energy is stored in simple systems. Examples could include:
vehicle braking systems (such as bike brakes)
a ball being thrown upwards
Presenting and writing descriptions and explanations:
Describe and explain what is happening in terms of changes in energy stores when a motor is used to raise a load. Ask students to explore questions such as:
When an object falls is the decrease in the gravitational potential energy store equal to the increase in the kinetic energy store?
Calculate:
Calculate the kinetic energy of a moving body.

Calculate the amount of energy stored by various objects including stretched springs and objects raised above the ground.

Calculation of an object’s speed given the kinetic energy of the object.

Calculate the speed of an object, just before impact, when dropped from a given height by equating the increase in the kinetic energy store to the decrease in the gravitational potential energy store.

Presenting and writing descriptions and explanations:
Explain the effect on the kinetic energy of an object when the speed and mass increases. In particular what will happen to the kinetic energy when the speed doubles and when the mass doubles?
Application and implication:
Explain the effect of increasing the spring constant of a spring on the ease that it stretches and on the amount of energy stored in the spring. Ask students to explore questions such as:
What determines how fast the temperature of a substance increases?
Presenting and writing descriptions and explanations:
Describe how the energy stored in a system changes when it is heated.

Calculate:
Calculate the increase in stored energy when a substance is heated.

Presenting and writing descriptions and explanations:
Describe what is happening at an atomic level when a substance is heated.

Developing explanations using ideas and models:
Give students an opportunity to create their own models to explain what is happening when a solid is heated. This can be in the form of a diagram, a 2D or 3D model as they see fit.

Calculate:
Carry out calculations involving specific heat capacity. Students should also be able to rearrange the equation to find any unknown in the equation.

Presenting and writing arguments:
Evaluate the use of concrete in storage heaters:
Why is concrete used?
What are the problems associated with the use of concrete?
Why aren’t other materials with a higher or lower specific heat capacity used? Applications, implications and cultural understanding. Developing argument:
Evaluate the benefits and drawbacks of using lower power devices such as compact fluorescent lamps (CFLs).

Calculations:
Carry out calculations to determine power, using energy transferred divided by time and work done divided by time.
4.1.2 Conservation and dissipation of energy Taught Practiced Mastered
Ask students to explore questions such as:
Can energy be created or destroyed?
What is meant when people say ‘energy is lost’?
How can we reduce the amount of energy being wasted by a machine?
What is the best way to reduce heat loss in the home?
Presenting and writing descriptions and explanations:
Presenting and writing arguments:
Describe, in terms of energy stores/work done, what happens when an appliance (such as a radio) is working.
Evaluate the use of various types of insulation in the home. Look in particular at the effectiveness of loft insulation and cavity wall insulation.
Communication for audience and purpose:
Design a poster to illustrate the reasons why insulating the home is beneficial for both the homeowner and the environment. Select specific examples and suggest what could happen if insulation was not used in the home. Ask students to explore questions such as:
Which type of power station is the most efficient?
Which type of light bulb would cost the least amount of money to use?
Research different types of power station to find out if combustion based power stations are less efficient that either nuclear or wind. Investigate ways of increasing the efficiency of a coal fired power station.

Prepare a presentation on different types of light bulb. Find out the cost of buying and running the light bulbs in a home for one year. Determine whether energy saving light bulbs will save money over incandescent light bulbs.

State the equations used to find efficiency.

Calculate the efficiency of a machine as either a decimal or a percentage.
Rearrange the equation to determine the total power input the machine or the useful power output.

Students may have to analyse data to determine the useful energy output if they are told the energy input and the amount of wasted energy.

Interpret data on efficiencies of different machines.
4.1.3 National and global energy resources Taught Practiced Mastered
Define renewable energy resource and give examples of them.

Define non-renewable energy resource and give examples of them.

Describe the way in which different energy resources are used and identify patterns and trends in the use of energy resources.

Research the different types of energy resources that are available to generate electricity.
For each type of energy resource find the environmental impacts. Explain why each type of energy resource is used to generate electricity even though it does have these environmental impacts.

For a given location determine the best way of generating electricity.
Role-play a meeting between a group of local councillors/MPs, local environmental groups and electricity companies trying to get a new power station built. Which type of power station would each group want? How persuasive are each group in getting their choice?
Evaluate the use of different energy resources for a given situation, e.g. generating electricity in remote locations. The evaluation should include ethical and environmental issues.

Compare the use of different fuels for heating homes and transport. Determine the most suitable fuel for a particular use depending on the characteristics of the fuel.

Identify the political, social, ethical and economic considerations that may arise from the use of different energy resources.