Level+2+Physics

ncea.govt.nz
 * **__ [|Level 2] __**
 * __ [|2.1 Physical quantities] __
 * __ [|2.3 Waves] __
 * __ [|2.4 Mechanics] __
 * __ [|2.5 Atoms and radioactivity] __
 * __ [|2.6 Electricity and electromagnetism] __
 * __ [|2.7 Integrated physics] __

[] looks at the anatomy of a firework

Absolute uncertainty

Also known as absolute error.

The uncertainty in a measured quantity is due to inherent variations in the measurement process itself. The uncertainty in a result is due to the combined and accumulated effects of these measurement uncertainties that were used in the calculation of that result. When these uncertainties are expressed in the same units as the measured value itself they are called absolute uncertainties. Uncertainty values are usually expressed:

(measured value) ± (absolute uncertainty in that quantity).



Adequate report
Your report will include evidence that you have:


 * followed a design in which you have:
 * an aim/testable question
 * a method
 * identified __ [|variables] __ – independent variable, dependent variable, and some fixed variables


 * collected information
 * recorded information
 * processed information
 * interpreted information or made a conclusion on information from the investigation.

Analyse
You are required to __ [|apply] __ understanding to some information that you are given.

Example of an analyse question:

The lens is focused on an object only 0.45 m away. You will notice that the lens is now further away from the camera body (and the film). Discuss, with the help of ray diagram(s) drawn in the boxes below, why the lens must be further way to form an image on the film when the object is this close to the camera.

Appropriate processing
This means that you have used a processing method that is suitable for the type of field data, to ensure that any relationship or pattern in the field data will be meaningful and accurate. You could show the relationship or pattern as a kite diagram, a bar graph, a pie chart, a profile diagram, or a table. Note that only one format is required to show an interrelationship or pattern.

Apply understanding
This means you are required to solve problems by applying acquired knowledge, facts, techniques, and rules in a different way. The question will involve some information, for example as words, a chart, a drawing, or a graph, that you will have to consider. Use the information to answer the question.

Example: 'Examine the periodic table. Apply your knowledge and describe two trends between the properties of metals and properties of non-metals.'

Example: 'Use the information in the diagram to discuss how diorite can be distinguished from basalt.'

Bias
Bias refers to a factor of sampling of the __ [|variables] __ of an investigation when the conclusions obtained from the investigation do not accurately describe the characteristics of the whole population. That is, the differences between the sample and the whole population are not just from random chance.

For example, bias may be caused by faulty measuring devices such as a tape measure that has been stretched, so that all measurements are too small.

Complex problem
A complex problem will involve more than one __ [|process] __. The recognition of at least two different concepts must be involved.

Comprehensive report
Your report will include evidence that you have:


 * designed a plan for your practical investigation
 * trialled and modified, if required
 * followed a __ [|justified design] __, with repeats, which has:
 * an aim/testable question
 * a method
 * independent variables with ranges
 * dependent variables
 * most fixed variables with values


 * collected sufficient and reliable information, ignoring extremes, recording repeats to confirm the accuracy of the information
 * recorded information systematically
 * processed information using averages and/or graphs
 * interpreted information from the investigation
 * a conclusion relating to aim/testable question
 * discussion relating to the science ideas AND evaluation of the investigation.

and

Computational error
An error that relates to a mathematical calculation

Examples:

An error created when cancelling incorrectly.

An error when entering the numbers into a calculator.



Conclusion
A conclusion links to the aim of the experiment and is drawn from information calculated from the linear graph.



Correlation
A correlation involves:


 * how data for the two variables will be collected and processed
 * an indication of the proposed range of the variables
 * mention of some other variables or factors that could influence the investigation.



Describe
This means you are required to recognise, list, name, draw, define or give characteristics of or an account of.

Example:

'What distance had Jim travelled at six seconds?' (from reading a graph)



Design a __ [|practical investigation] __
At NCEA level one, you were directed to plan a practical investigation with direction. At NCEA level two, you are required, with supervision, to design a practical investigation. This means that you will individually be able to prepare a plan of a practical investigation and show to your teacher the steps you will take to carry out the investigation. This means that you will:


 * state the purpose of your investigation
 * make a hypothesis
 * decide on an experimental procedure that will test the hypothesis
 * Identify the key factors that will be studied
 * identify the equipment and materials you will need decide how you will use them.



Detailed method
A detailed method is achieved if your method includes sufficient detail and clarity of instruction for others to carry out the experiment and achieve consistent outcomes.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Develop the investigation
This means you must demonstrate in your investigation some form of trialing or checking before developing your initial plan into a method.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Difference between data and information
Data is factual information, especially information that is used for analysis or reasoning. Data on its own has no meaning, but becomes information when it is interpreted and placed in a context. Information is a collection of facts or data. However, often the terms data and information are used interchangeably as synonyms.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Directed use of graphs and diagrams
This means that you will be required to read information directly from graphs and diagrams (including __ [|interpolate] __ and __ [|extrapolate] __ values) or draw graphs or diagrams from given information.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Discuss
This instruction requires you to show understanding by linking scientific ideas. It may involve you to elaborate, apply, justify, relate, evaluate, compare and contrast, analyse.

Example:

'Compare the amount of work done by the engine of the bus to the gravitational potential energy gained by the bus. Discuss any differences.'



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Discussion (about a conclusion to an experiment)
A discussion may include limitations of the experiment, other variables that had not been foreseen, difficulties in measuring, difficulties in the use of equipment, limitations of the findings and impact on the outcome.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Error (in an investigation)
Sources of error can come from human error while carrying out each measurement (for example parallax error) and from the equipment you use. You can minimise error by carrying out several measurements and using the average of your measurements as your data. However, if the differences between repeat trials are too large, then you may need to look at improving or modifying your investigation.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Evaluate
To evaluate something means you need to show understanding by considering, discussing, analysing, judging, or assessing the importance of a scientific idea. You will be able to base this on a sound knowledge of facts (from your reading or from a data collection).



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Evaluate (researched information)
Evaluate requires you to:


 * comment on sources and information, considering ideas such as validity (date, peer reviewed, scientific acceptance), bias (attitudes, values, beliefs), weighing up how science ideas are used by different groups, own opinions, attitudes and beliefs
 * provide a justified position that supports or opposes aspects of the issue or an implication of the issue. Justified means to demonstrate, with supporting evidence, why the position has been chosen.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Explain
This instruction involves describing as well as giving reasons as to how or why something occurs.

Examples:

'Explain what the results of this investigation show.'

'Calculate Jim's average speed over the whole 11 second journey. (m s -1 )'



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Extrapolate
This means to extend a range of values for a graph or curve based on trends of existing values.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Fair test
A fair test involves:


 * identification of the dependent and independent variables
 * the range of the independent variables
 * some other variables to be fixed or controlled
 * how the dependent variable will be measured and the data processed.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Feasible investigation
A feasible investigation means that you have designed a plan that:


 * states a purpose, which might be an aim, testable question, prediction or hypothesis, linked to a scientific concept or idea
 * has a scientific method to collect relevant data so that a report can be written. The method identifies:
 * the key variables or data to be measured or collected. Key variables will be the dependent and independent variables for a fair test or data/samples to be collected when investigating a pattern or relationship, for example, for biology – zonation. Other variables that need to be controlled or other factors that could influence the investigation will also be identified.

However, the method lacks some detail and cannot be independently followed without further clarification.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Feasible method
A feasible method is achieved if you have provided a means for changing the independent variable and for measuring the dependent variable, and you have shown awareness that there may be other variables that could affect the results.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Feasible plan
A feasible plan is a plan that looks like it will work but does not have a lot of detail. Compare to a __ [|workable plan] __.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Fully process data
Fully process data involves transforming __ [|sufficient raw data/results] __ to produce a linear graph that shows correctly labelled (including unit) axes and an error line.

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Historical development of a scientific idea
For the historical development of a scientific idea, information should:
 * give details of the model(s) or view(s) at given times
 * state new observations or experimental evidence that refined previous model(s) or view(s)
 * show how accepted model(s) or view(s) were changed to accommodate the new evidence.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Hypothesis
A statement that you will test to prove or disprove in a __ [|practical investigation] __. Check out more information with examples on the website__ Problem and Hypothesis __. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Identify
Be able to select correctly or match to some description or part of a diagram, from information given to you. Example of an identify question: Draw the flat mirror so that it will reflect the light ray into the pentaprism along the path shown in the diagram. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Integrate (researched information)
Integrate means that you bring together and organise relevant information and opinions from a range of sources. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Interpolate
In mathematics this means to estimate a value by calculating it from surrounding values. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Interpret
This instruction requires you to provide reasons for how and why, or to explain with reason. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Interpreting and reporting information

 * Appropriate formats could include: booklets, brochures, posters, flow charts or annotated timelines with supporting notes or visual and/or oral reports.
 * In your report, you will be expected to interpret the processed information in your own words and comment on your findings.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Interpretation
An interpretation is made as a result of thinking about some information such as a graph and expressing your ideas in some way. Example: 'Make an interpretation of the time graph.'  ====<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Interpretation and reporting the findings (of a __ [|practical investigation] __) ==== This means you have reported the findings and processed the data appropiately. Intepretation of the data must relate to the purpose of your investigation. The report follows the format clearly specified in written guidelines by your teacher and would usually include the following sections:
 * plan, including the purpose of the investigation and final method used
 * recorded data
 * processed data, showing links to the recorded data
 * interpretations and a conclusion, including a generalised statement linking the findings of the investigation with the purpose of the investigation
 * evaluation or discussion, which may include limitations of the investigation, other variables that had not been foreseen, difficulties in measuring, difficulties in the use of equipment, limitations of the findings, and impact on the outcome, and, where relevant, suggested solutions or pathways for further investigation and links to science concepts or ideas.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Justified
Explained with reason(s).

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Justified conclusion
A conclusion is justified if it is relevant to the aim of the experiment, it is based on the data, and the calculated information from which it is drawn has a processed uncertainty that includes an uncertainty in the graph. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Knowledge-based questions
These questions rely on your ability to recall information.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Link
This requires you to show a relationship between two things or situations, especially where one thing affects another.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Observation
An observation is made by using your senses, for example by looking at, hearing, thinking about, touching, or smelling something. Example: 'Give an observation that Jill would make if she added red litmus to potassium hydroxide.' Your answer may simply state that 'Jill will observe a colour change of the litmus paper from red to blue/purple.' 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Parallax error
A parallax error can be introduced when you carry out a measurement if you do not read the instrument directly from its front. This is because the indicator may be separated from the scale. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Percentage uncertainty
Also known as relative uncertainty. The uncertainty of a measurement is compared to the measured value itself, usually expressed as a percentage ratio of the absolute uncertainty to the size of the quantity. For example: 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Planning a __ [|practical investigation] __
In science, the plan of an investigation will contain the purpose of the investigation. This may include an aim, testable question, prediction, or hypothesis based on a scientific idea. A plan will involve some form of trialling or checking of the plan so it can be adapted if required. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Practical investigation
An investigation is an activity covering the complete process: planning, collecting and processing data, interpreting, and reporting on the investigation. It will involve the student in the collection of primary data. A practical investigation will involve:
 * a statement of the purpose – this may be an aim, prediction, or hypothesis based on a scientific idea
 * identification of a range for the independent variable or sample
 * measurement of the dependent variable or the collection of data
 * collecting, recording and processing data relevant to the purpose
 * a conclusion based on interpretation of the processed data.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Precision
When you repeat a measurement in one practical investigation on the same parameter, you may find that readings will be different from each other. The cause may be: You are advised to use or quote the average of the readings as the best value. However, it is also a good idea to fins the variability of your readings. You can do this by: 
 * a small difference in the way you use the instrument each time, or
 * random changes in the instrument, due to small changes in the parameter you are measuring.
 * finding the range of values you have measured, i.e. the difference between the largest and smallest reading, or better still by
 * calculating the __ [|variance] __ of the readings. The bigger the variance the less precise is the reading, and the smaller the variance the more precise is the reading.

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Prediction
In a scientific investigation you need to say what you think will happen in your experiment using your scientific knowledge. This is called a prediction. For example: if you are going to measure lots of temperatures, explain why you are going to do this and what you expect to observe about the temperature. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Problem
A problem in physics involves __ [|process(es)] __ to find a physical quantity.
 * the relevant concept or principle is not immediately obvious
 * the method involves the use of a complex formula or rearrangement, or
 * the information is not directly usable or immediately obvious.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Process
A process in physics involves:
 * recognising the relevant concept or principle
 * selecting the method (for example, formula, graph, diagram, logical deduction)
 * selecting the relevant information.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Process data or information
To process data or information is about organising the data that you collect to make some sense. It may involve listing, sorting, collating, highlighting, reformatting, summarising, graphing, calculating etc. Processing data or information may involve calculations, for example, average a set of numbers or graph the data, to try to find a meaningful pattern or trend. Note that for the purpose of your school work, the words data and information mean the same. However, you might like to check out __ [|difference between data and information] __. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Qualitative data
Data that is collected, recorded and processed in an investigation may be qualitative or __ [|quantitative] __. Qualitative data provide labels, or names, for categories of like items, i.e. a set of observations where any single observation is a word or code that represents a class or category. Some examples of qualitative data would be: gender, colour, hot/cold, yes/no. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Quantitative data
Data that is collected, recorded and processed in an investigation may be__ [|qualitative] __ or quantitative. Quantitative data measures either how much or how many of something, i.e. a set of observations where any single observation is a number that represents an amount or a count. Some examples of quantitative data would be: weight, count, area, age. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 14px; line-height: 21px;">Referenced sources In carrying out your research you will get information from a number of different sources, such as articles, books, or websites. In your report you are required to provide a reference list which is made up of these sources. Each reference must be described in such a way that another person can locate, read and use each of the sources for information too. A reference can be used to:
 * validate any information that you write in your report
 * show to the assessor the amount of reading you have done about your research.



<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Reliability
You want to be sure that if someone else carried out your investigation they would get the same results and come to the same conclusions. Unreliable conclusions are worthless, other than telling you that your investigation should be modified and improved. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Research
In research, you will select data from sources where the data have been initially produced or collected by another person. This is secondary data. Examples of sources of secondary data may come from books, encyclopaedia, magazines, newspapers, other research articles/papers, or Internet addresses (URLs). The research process involves planning, collecting or gathering data/information, processing, interpreting, and presenting a report. Some use of primary sources, for example, through interviews, is acceptable. At NCEA level two, it is expected that you will carry out your own research and reference their material. At NCEA level three, it is expected that you will drive the research. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Resource-based questions
You will be given information about something or situation and will be required to answer questions relating to the thing or situation. Example of a resource-based question: Beer has certain flavours. Explain how the alcohol in beer improves the flavour of the beer that is produced. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Results of the research
Present the results of the research as a written report, newspaper article, seminar, video, web page, or power point presentation. 

<span style="font-family: Helvetica,Arial,sans-serif; font-size: 1.1em;">Scientific notation
<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Also known as Standard form or Standard index notation. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Scientific notation is a concise way of recording very large or very small numbers by integer powers of ten. Such notation is used to record physical quantities without including trailing, or leading, zeros:
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 1 = 10
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 2 = 100
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 3 = 1000
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 6 = 1,000,000
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 9 = 1,000,000,000
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 20 = 100,000,000,000,000,000,000

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Additionally, 10 raised to a negative integer power //-n// is equal to 1/10 //n// or, equivalently 0. //(n-1 zeros)1//: > =1/10= > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">0.1 > =1/1000= > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">0.1 > =1/1,000,000,000= > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">0.000000001 <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Thus: > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">A large number such as 156,234,000,000,000,000,000,000,000,000 can be concisely recorded as 1.56234 × 10 29, and a small number such as 0.0000000000234 can be written as 2.34 x 10 -11. > For example: > The distance to the edge of the observable universe is ~4.6 x 10 26 metres. The mass of a proton is ~1.67 x 10 -27 kg. > Most calculators and many computer programs present very large and very small results in scientific notation; the 10 is usually omitted and the letter E for exponent is used; for example: 1.56234 E29. Note that this is not related to the base of the natural logarithm that is also commonly denoted by //e//. > Scientific notation is highly useful for quoting physical quantities, as they can only be measured to within certain error limits and so quoting just the digits that are certain (the 'significant digits') gives all the information required without wasting space. > <span style="font-family: Arial,Helvetica,sans-serif;"> > ====<span style="font-family: Arial,Helvetica,sans-serif; font-size: 1.1em;">Scientific report ==== > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">A scientific report involves: > <span style="font-family: Arial,Helvetica,sans-serif;"> > ==== ==== > <span style="font-family: Arial,Helvetica,sans-serif;"> > ====<span style="font-family: Arial,Helvetica,sans-serif; font-size: 1.1em;">Significance of an idea or application ==== > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">This requires a description of the importance or impact the idea or application has on our understanding of physics and relates to the usefulness and effect of the idea or application on humans. > Example: > The significance of nuclear power to generate electricity is huge. While the use of nuclear power may solve our electricity shortage in New Zealand and it may reduce global warming, the management and storage of the radioactive by-products will have to be considered. > <span style="font-family: Arial,Helvetica,sans-serif;"> > ==== ==== > <span style="font-family: Arial,Helvetica,sans-serif;"> > ====<span style="font-family: Arial,Helvetica,sans-serif; font-size: 1.1em;">Straightforward problem (in physics) ==== > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">A straightforward problem involves a single __ [|process] __, where: > <span style="font-family: Arial,Helvetica,sans-serif;"> > ====<span style="font-family: Arial,Helvetica,sans-serif; font-size: 1.1em;">Sufficient data ==== > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Your collection of data involves repeats, trials, or an appropriate sample size and gives confidence to the conclusion of an experiment or investigation. > For example, if a physics investigation concludes with the identification of a relationship between variables, the assessor wants to be confident that if another investigation was carried out with the same method, that the data collected will result in the same conclusion. > <span style="font-family: Arial,Helvetica,sans-serif;"> > ====<span style="font-family: Arial,Helvetica,sans-serif; font-size: 1.1em;">Sufficient detailed information ==== > <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Collection of sufficient detailed information means that you have:
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 -1
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 -3
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">10 -9
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">presenting scientific interpretations of information appropriate to the topic
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">presenting material in a reporting format suitable for scientific information
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">acknowledging sources of information in a traceable reference system.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">the relevant concept or principle will be transparent
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">the method will be straightforward (a formula will need no more than a simple rearrangement), and
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">the information will be directly usable.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">enough data to draw valid conclusion(s), with a full range for the independent variable
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">recorded information systematically in a valid scientific format
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">recorded repeats.