# Applied Science AQA/Energy and Efficiency

## Topic Title

### Setting Applied context

It is useful for energy consultants to be able to compare the efficiency of different devices in our homes and workplaces. Energy is transferred by different devices, and the rate at which energy is transferred is called ‘power’.

Architects and energy consultants use U values to measure how effective different materials used in buildings are as insulators. That is, how effective they are at preventing heat energy from transmitting between the inside and the outside of a building.

Syllabus Content What you need to do
Efficiency

• the meaning of ‘efficiency’:

• why efficiency is important and why a device can never be 100% efficient

• methods of improving the efficiency of a system or device

• the formula ${\displaystyle efficiency={\frac {usefulenergy(orpower)output}{usefulenergy(orpower)input}}}$

• the importance of efficiency in making the best use of available energy

• ways in which efficiency can be increased in mechanical and thermal systems

• Work out the efficiency.
• explain the term
• why is efficiency useful?
U-Values

• examples of situations where thermal transfer needs to be maximised and situations where it needs to be minimised

• the meaning of U values

• the formula ${\displaystyle U={\frac {Q}{At{\vartriangle }T}}}$

### Exploration of key ideas (must be original text, not C&P) – level checked by AQA

In general, point students towards the approach to take, as opposed to just giving them information.

#### The meaning of efficiency

Efficiency is a measure of how much work or energy is kept and not lost in a process. in many processes, work or the energy is lost, this can be through heat or sound. the efficiency is the energy output, this is divided by the energy input and is expressed as a percentage. A perfect process would of an efficiency of 100%.

explanation 2

explanation 3

#### Concept 4

explanation 4

Work to do to understand this topic e.g. research, analysis

### Careers and Organisations

Carry out some research into these jobs in this area. (Feel free to add other jobs you find.)

Research these roles: What are the benefits of this role to society? What organisations would employ someone in this role?

(Where would they work?)

What would someone in this role have to do within the organisation? What scientifically-related skills do they need to have?

What techniques do they need to have mastered?

What experience is needed to undertake this role and its responsibilities within an organisation? What other science personnel will they work with in their organisation.
Job 1
Job 2

### Relevant practical/s

– relating to criteria skills

### Quick questions

Example:

quick questions

Solution

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### Exam-style questions

– can we use old AQA qs… e.g. from more than 5 years ago? With Examiner comments

Solution

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