What is the difference between quantitative and qualitative data?

Quantitative data uses numerical values. Qualitative data is observed but not measured with a numerical value (e.g. colour).

In a table of results, to how many significant figures or decimal places should each reading be recorded?

Usually the same number as the resolution of the measuring instrument used.

What is the correct column order for presenting data in a table of results?

The independent variable first, then the dependent variable (with any repeats and their mean ), then any columns of processed or calculated data.

In a table, the quantity and unit of a column heading should be separated by a .......... .

In a table, the quantity and unit of a column heading should be separated by a forward slash ( / ) .

How should each of the following types of data be displayed on a graph or chart? Discrete , continuous , categorical , ordered

Discrete (e.g. number of students) — scatter graph or bar chart. Continuous (e.g. voltage) — line or scatter graph. Categorical (e.g. types of material) — pie or bar chart. Ordered (e.g. low, medium, high) — bar chart.

True or False? Suspected anomalous results should be left off a graph when the data is plotted.

False. All readings, including suspected anomalies, should be plotted so that they can be easily identified.

When repeat readings are taken for the dependent variable, what value should be plotted on the graph?

The mean value of the repeat readings.

What rule applies to the number of significant figures used within a single column of data in a table?

All the data in that column should be quoted to the same number of significant figures.

When calculating a mean from several repeat readings, how many significant figures should the mean be quoted to?

It is acceptable to increase the number of significant figures of the mean by one , compared with the raw readings.

How can the area under a graph that is not linear be found?

It is estimated , since a simple straight-line formula cannot be used.

How can the instantaneous velocity at a point on a curved displacement-time graph be found?

By drawing a tangent to the curve at that point and calculating its gradient .

List the graph skills expected during A Level Physics, beyond calculating the gradient of a straight-line graph.

Finding the area under a graph (including estimating non-linear areas); using and interpreting logarithmic plots ; drawing tangents and calculating their gradient; understanding where asymptotes may be required.

True or False? Standard form is only useful for writing very large physical quantities, not very small ones.

False. Standard form is used to present numbers that are very large or very small, without having to repeat many zeros.

What proportion of the graph grid should be occupied by the plotted data, in both the x and y directions?

At least half (50%) of the grid, in both directions.

How should the quantity and unit be shown when labelling a graph axis, e.g. for force?

As the quantity name followed by a forward slash and the unit, e.g. F / N.

On a graph, the .......... variable is plotted on the x-axis, and the dependent variable is plotted on the y-axis.

On a graph, the independent variable is plotted on the x-axis, and the dependent variable is plotted on the y-axis.

True or False? A line of best fit should always be forced through the origin.

False. Not all lines pass through the origin, and the line of best fit should not be forced to.

When calculating a gradient from a graph, how large should the triangle used be?

As large as possible — small triangles are not acceptable.

How is the gradient of a line calculated from a graph?

By dividing the rise (change in y) by the run (change in x).

What is a y-intercept ?

The y value where a line crosses the y-axis, at x = 0.

What is the difference between evaluating experimental results and evaluating experimental procedure?

They are different skills — evaluating results assesses the data obtained, while evaluating procedure assesses the method used to obtain it.

When can conclusions be drawn from experimental results?

Only once the results have been properly evaluated .

How does the impact of experimental limitations affect the conclusions that can be drawn?

If the impact is judged negligible , a conclusion can more confidently be drawn. If the impact is judged significant , it is harder to draw a conclusion, and any conclusion drawn is more likely to be incorrect .

At what stage in the experimental process should limitations of a procedure ideally be identified?

During the planning stage, before the experiment is carried out.

An anomaly is a result caused by an experimental (operator) error that does not fit the trend or other replicates.

What numerical threshold is often used to identify a result as anomalous?

A result is often considered anomalous if it differs from the mean by more than 10% .

If an anomaly occurs during an experiment, it should be .......... when calculating the mean, and the measurement should be repeated.

If an anomaly occurs during an experiment, it should be ignored when calculating the mean, and the measurement should be repeated.

True or False? Removing identified anomalies and repeating an experiment makes the results less reliable.

False. Repeating the experiment and removing anomalies makes the results more reliable , allowing more valid conclusions to be drawn.

What key details must be recorded in written instructions for an experiment?

The aims of the investigation, the variables investigated, the apparatus used, and the step-by-step method .

Written instructions for an experiment should allow it to be carried out in what way?

Independently , without any additional help or input.

True or False? Saying "the time wasn't measured very accurately" is an example of a precise, scientific observation.

False. This is vague and ambiguous language. A more appropriate statement identifies the specific source of error, e.g. "using a stopwatch introduced an error due to the experimenter's reaction time".

When recording a reading from a digital measuring device (e.g. a top pan balance), how many digits should be recorded?

All the digits shown on the display.

What is the exception to recording all the digits shown on a digital device?

For a digital timer (e.g. a stopwatch), there is no need to record to more than two decimal places .

When using a non-digital measuring device such as a ruler, all known figures should be recorded, and where appropriate, one additional .......... figure may be allowed.

When using a non-digital measuring device such as a ruler, all known figures should be recorded, and where appropriate, one additional estimated figure may be allowed.

What should records made during a laboratory session be treated as?

The primary evidence of the outcomes of the experiment.

What must a written record of an experiment include, aside from the measurements or observations?

Analysis of the raw data (graphs or calculations), the conclusions drawn, and an evaluation of the experiment (e.g. errors or limitations).

When does the method not necessarily need to be included in a written record of an experiment?

Unless an investigative approach is taken, where the student develops part of the procedure themselves.

What three things must be included when presenting data in a table?

Clear headings (or symbols) for columns, relevant units for measurements, and readings listed to the same number of significant figures .

Name the five things that must be included when presenting a graph.

An explanatory title , clearly labelled axes , relevant units for measurements, well plotted points , and a smooth line or curve of best fit .

When presenting a diagram, such as an apparatus set-up, what must be included?

All the relevant parts of the diagram must be clearly labelled .

When presenting a table of results, the readings should be listed to the .......... number of significant figures.

When presenting a table of results, the readings should be listed to the same number of significant figures.

True or False? A graph does not need an explanatory title as long as the axes are labelled.

False. A graph must include an explanatory title , as well as clearly labelled axes.

What is a data logger used for?

A data logger is an electronic device that is used to automatically record multiple readings per second and display them as a graph or table in real time.

Why is the use of electronic software and tools in experiments beneficial?

It improves accuracy and removes sources of uncertainty such as human error.

What type of software is particularly useful for processing large amounts of experimental data?

Spreadsheet software, such as Microsoft Excel, provides an effective way of plotting graphs and analysing large data sets.

How can a camera be used in an experiment that happens too quickly to read a scale directly?

A photo burst is taken during the experiment and the scale is read from the photos afterwards. If the time of each photo, or the frame rate, is known, properties such as velocity can be calculated.

Electronic data loggers are more accurate, quick and reliable than .......... logging.

Electronic data loggers are more accurate, quick and reliable than manual logging.

True or False? Spreadsheets are only useful when the amount of experimental data is small.

False. Spreadsheets provide an effective way of processing data and are particularly useful when the amount of data is large .

Name three suitable sources for researching a practical.

Books and textbooks, scientific articles and journals, and reputable websites.

A LevelPhysicsOCRFlashcards1. Development of Practical Skills in PhysicsHandling Data

Handling Data (OCR A Level Physics): Flashcards

Exam code: H556

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FrontPresenting & Interpreting Results
What is the difference between quantitative and qualitative data?

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Cards in this collection (81)

What is the difference between quantitative and qualitative data?
Quantitative data uses numerical values. Qualitative data is observed but not measured with a numerical value (e.g. colour).
In a table of results, to how many significant figures or decimal places should each reading be recorded?
Usually the same number as the resolution of the measuring instrument used.
What is the correct column order for presenting data in a table of results?
The independent variable first, then the dependent variable (with any repeats and their mean), then any columns of processed or calculated data.
In a table, the quantity and unit of a column heading should be separated by a ...........
In a table, the quantity and unit of a column heading should be separated by a forward slash ( / ).
How should each of the following types of data be displayed on a graph or chart?
Discrete, continuous, categorical, ordered
Discrete (e.g. number of students) — scatter graph or bar chart.
Continuous (e.g. voltage) — line or scatter graph.
Categorical (e.g. types of material) — pie or bar chart.
Ordered (e.g. low, medium, high) — bar chart.
True or False?
Suspected anomalous results should be left off a graph when the data is plotted.
False.
All readings, including suspected anomalies, should be plotted so that they can be easily identified.
When repeat readings are taken for the dependent variable, what value should be plotted on the graph?
The mean value of the repeat readings.
How is experimental data often processed to test whether it follows a particular relationship, such as an inverse square law?
The data is manipulated so that it can be compared to the equation of a straight line, $y = m x + c$ ; if the processed data produces a straight line, the relationship is confirmed.
What rule applies to the number of significant figures used within a single column of data in a table?
All the data in that column should be quoted to the same number of significant figures.
When calculating a mean from several repeat readings, how many significant figures should the mean be quoted to?
It is acceptable to increase the number of significant figures of the mean by one, compared with the raw readings.
If a relationship obeys the straight-line equation $y = m x + c$ , the .......... and the y-intercept can be found and analysed to draw conclusions.
If a relationship obeys the straight-line equation $y = m x + c$ , the gradient and the y-intercept can be found and analysed to draw conclusions.
How can the area under a graph that is not linear be found?
It is estimated, since a simple straight-line formula cannot be used.
How can the instantaneous velocity at a point on a curved displacement-time graph be found?
By drawing a tangent to the curve at that point and calculating its gradient.
List the graph skills expected during A Level Physics, beyond calculating the gradient of a straight-line graph.
Finding the area under a graph (including estimating non-linear areas); using and interpreting logarithmic plots; drawing tangents and calculating their gradient; understanding where asymptotes may be required.
True or False?
Standard form is only useful for writing very large physical quantities, not very small ones.
False.
Standard form is used to present numbers that are very large or very small, without having to repeat many zeros.
What proportion of the graph grid should be occupied by the plotted data, in both the x and y directions?
At least half (50%) of the grid, in both directions.
How should the quantity and unit be shown when labelling a graph axis, e.g. for force?
As the quantity name followed by a forward slash and the unit, e.g. F / N.
On a graph, the .......... variable is plotted on the x-axis, and the dependent variable is plotted on the y-axis.
On a graph, the independent variable is plotted on the x-axis, and the dependent variable is plotted on the y-axis.
To what precision should data points be plotted on a graph?
Within half a small square.
What is the minimum number of points that should be plotted on a graph?
At least six points.
True or False?
A line of best fit should always be forced through the origin.
False.
Not all lines pass through the origin, and the line of best fit should not be forced to.
When calculating a gradient from a graph, how large should the triangle used be?
As large as possible — small triangles are not acceptable.
How is the gradient of a line calculated from a graph?
By dividing the rise (change in y) by the run (change in x).
What is a y-intercept?
The y value where a line crosses the y-axis, at x = 0.
What is the difference between evaluating experimental results and evaluating experimental procedure?
They are different skills — evaluating results assesses the data obtained, while evaluating procedure assesses the method used to obtain it.
When can conclusions be drawn from experimental results?
Only once the results have been properly evaluated.
How does the impact of experimental limitations affect the conclusions that can be drawn?
If the impact is judged negligible, a conclusion can more confidently be drawn. If the impact is judged significant, it is harder to draw a conclusion, and any conclusion drawn is more likely to be incorrect.
At what stage in the experimental process should limitations of a procedure ideally be identified?
During the planning stage, before the experiment is carried out.
Define an anomaly.
An anomaly is a result caused by an experimental (operator) error that does not fit the trend or other replicates.
What numerical threshold is often used to identify a result as anomalous?
A result is often considered anomalous if it differs from the mean by more than 10%.
If an anomaly occurs during an experiment, it should be .......... when calculating the mean, and the measurement should be repeated.
If an anomaly occurs during an experiment, it should be ignored when calculating the mean, and the measurement should be repeated.
True or False?
Removing identified anomalies and repeating an experiment makes the results less reliable.
False.
Repeating the experiment and removing anomalies makes the results more reliable, allowing more valid conclusions to be drawn.
What key details must be recorded in written instructions for an experiment?
The aims of the investigation, the variables investigated, the apparatus used, and the step-by-step method.
Written instructions for an experiment should allow it to be carried out in what way?
Independently, without any additional help or input.
True or False?
Saying "the time wasn't measured very accurately" is an example of a precise, scientific observation.
False.
This is vague and ambiguous language. A more appropriate statement identifies the specific source of error, e.g. "using a stopwatch introduced an error due to the experimenter's reaction time".
When recording a reading from a digital measuring device (e.g. a top pan balance), how many digits should be recorded?
All the digits shown on the display.
What is the exception to recording all the digits shown on a digital device?
For a digital timer (e.g. a stopwatch), there is no need to record to more than two decimal places.
When using a non-digital measuring device such as a ruler, all known figures should be recorded, and where appropriate, one additional .......... figure may be allowed.
When using a non-digital measuring device such as a ruler, all known figures should be recorded, and where appropriate, one additional estimated figure may be allowed.
What should records made during a laboratory session be treated as?
The primary evidence of the outcomes of the experiment.
What must a written record of an experiment include, aside from the measurements or observations?
Analysis of the raw data (graphs or calculations), the conclusions drawn, and an evaluation of the experiment (e.g. errors or limitations).
When does the method not necessarily need to be included in a written record of an experiment?
Unless an investigative approach is taken, where the student develops part of the procedure themselves.
What three things must be included when presenting data in a table?
Clear headings (or symbols) for columns, relevant units for measurements, and readings listed to the same number of significant figures.
Name the five things that must be included when presenting a graph.
An explanatory title, clearly labelled axes, relevant units for measurements, well plotted points, and a smooth line or curve of best fit.
When presenting a diagram, such as an apparatus set-up, what must be included?
All the relevant parts of the diagram must be clearly labelled.
When presenting a table of results, the readings should be listed to the .......... number of significant figures.
When presenting a table of results, the readings should be listed to the same number of significant figures.
True or False?
A graph does not need an explanatory title as long as the axes are labelled.
False.
A graph must include an explanatory title, as well as clearly labelled axes.
What is a data logger used for?
A data logger is an electronic device that is used to automatically record multiple readings per second and display them as a graph or table in real time.
Why is the use of electronic software and tools in experiments beneficial?
It improves accuracy and removes sources of uncertainty such as human error.
What type of software is particularly useful for processing large amounts of experimental data?
Spreadsheet software, such as Microsoft Excel, provides an effective way of plotting graphs and analysing large data sets.
How can a camera be used in an experiment that happens too quickly to read a scale directly?
A photo burst is taken during the experiment and the scale is read from the photos afterwards. If the time of each photo, or the frame rate, is known, properties such as velocity can be calculated.
Electronic data loggers are more accurate, quick and reliable than .......... logging.
Electronic data loggers are more accurate, quick and reliable than manual logging.
True or False?
Spreadsheets are only useful when the amount of experimental data is small.
False.
Spreadsheets provide an effective way of processing data and are particularly useful when the amount of data is large.
Name three suitable sources for researching a practical.
Books and textbooks, scientific articles and journals, and reputable websites.
Which resource is ideal for carrying out a risk assessment for a practical?
The CLEAPSS Student Safety Sheets.
Define a citation.
A citation is a quotation or reference to an academic text included within a practical report.
What information must be included when citing a book?
Author(s), book title, chapter and page numbers, edition (if relevant), date published and publisher.
What information must be included when citing a website?
Author(s), website title, date written, URL and date accessed.
If a book does not have named authors or editors, the reference begins with the ...........
If a book does not have named authors or editors, the reference begins with the title.
True or False?
When citing a scientific article, the journal's volume and issue numbers are not required.
False.
Referencing an article requires the author(s), article title, date published and journal, including the volume number, issue number and page numbers.
Define precision.
Precision is how close a set of repeated measurements are to each other.
Define accuracy.
Accuracy is how close a measured value is to the true value.
How can random error be reduced?
By repeating measurements several times and calculating an average (mean) from them.
How can systematic error be reduced?
By recalibrating the instrument, or correcting/adjusting the technique being used.
What is a zero error?
A systematic error that occurs when an instrument gives a reading when the true reading is zero.
The uncertainty in a reading from an analogue instrument is .......... the smallest scale division of that instrument.
The uncertainty in a reading from an analogue instrument is half the smallest scale division of that instrument.
Give three examples of limitations in an experimental procedure.
Parallax error when reading scales, not using a fiducial marker, not repeating measurements, not checking for zero errors, poor precision or resolution of equipment, difficulty controlling variables, and unwanted heating effects.
True or False?
If a set of repeated measurements are close together, the experiment must be accurate.
False.
Close repeated measurements indicate precision, not necessarily accuracy — the readings could share the same systematic error and still be far from the true value.
Define significant figures.
Significant figures are the digits in a number that are reliable and absolutely necessary to indicate the quantity of that number.
Are zeros between non-zero digits significant?
Yes — for example, 4107 has 4 significant figures.
Are zeros that come before all non-zero digits significant?
No — for example, 0.00079 has 2 significant figures.
Are zeros after non-zero digits significant in a whole number written without a decimal point?
No — for example, 57 000 has 2 significant figures.
Are zeros after non-zero digits significant in a number written with a decimal point?
Yes — for example, 689.0023 has 7 significant figures.
When rounding to a given number of significant figures, if the next digit (the '..........') is 5 or greater, the previous value is increased by 1.
When rounding to a given number of significant figures, if the next digit (the 'rounder decider') is 5 or greater, the previous value is increased by 1.
True or False?
The number 640 has three significant figures.
False.
640 has two significant figures — a zero after a non-zero digit in a whole number without a decimal point is not significant.
Name three methods used to reduce uncertainty in an experimental method.
Timing over multiple oscillations, using a fiducial marker, and using a set square or plumb line.
Why is it better to time multiple oscillations of a pendulum rather than a single oscillation?
Measuring many oscillations and dividing the total time by the number of oscillations reduces the uncertainty in the calculated time period.
Define a fiducial marker.
A fiducial marker is a fixed reference point used to improve the accuracy of timing measurements, such as sighting a pendulum as it passes the marker.
At what point in its swing should a pendulum be timed against a fiducial marker, and why?
At its lowest point, because the pendulum is moving at its highest speed there, making the timing more precise.
What is a set square used to check?
Whether an object is vertical, whether two objects are at right angles to each other, or whether two lines are parallel.
A .......... can be used to check whether an experimental setup is vertically aligned.
A plumb line can be used to check whether an experimental setup is vertically aligned.
True or False?
A plumb line is used to check whether two lines are parallel.
False.
Checking whether two lines are parallel is done with a set square; a plumb line checks whether a setup is vertically aligned.

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