Substituting the assumed form of the electric field (Equation 7.20) into the empty-space version of Gauss's law (Equation 7.16) gives

The first two partial derivatives are equal to zero because f does not depend on x or y. So we obtain

Author(s): The Open University

Information is everywhere these days â€“ in the form of images, written records, tables and graphs. In this part of the unit we want you to realise how useful graphs can be to analyse numerical information, and to show you some techniques that can help you decide how reliable this numerical information is.

It's often difficult to spot a trend or a relationship in a long list of numbers. Because the human mind is highly adapted to recognising visual patterns, it is often much easier to u
Author(s): The Open University

Figure 2 shows a picture of a ruler. The major units are marked in centimetres (1 to 11 cm), whilst the intervals between the centimetres have each been split into ten equal, smaller units. These minor units are therefore tenths of a centimetre, commonly known as â€˜millimetresâ€™. (There are 10 millimetres in 1 centimetre
Author(s): The Open University

Simple rules for dealing with orders of magnitude and decimal points in decimal numbers: values ten times bigger than the order of magnitude you are looking at go to the left, ten times smaller go to the right, and less than 1 to the right of the decimal point.

Note: in many European countries, a comma is used instead of a decimal point. For instance in France and Germany two and a half (in other words 2.5) can be written as 2,5. This is important to bear in mind, for example, if
Author(s): The Open University

Suppose you have less than one of any particular unit: how would you represent that using the decimal system?

Well, we've already seen that decimal numbers rely on a positional system, in which values get smaller by factors of ten as you read from left to right. If we continue doing this, then the number to the right of a single unit represents tenths of that unit. A decimal point is then used to mark the boundary between the whole units and tenths of that unit.

For instanc
Author(s): The Open University

Many different systems for writing numbers have been developed over the history of humankind.

The easiest way of counting small numbers is to use your fingers, and for this reason many numerical systems, such as the decimal system, are based around the number ten. But what happens when you run out of fingers to count on?

Numbering systems get round this problem by using a system of scale in which many small units are represented by a single larger unit, and many of these la
Author(s): The Open University

By the end of this unit you should be able to:

• understand the decimal system of numbering (hundreds, tens, units);

• explain the best way to write down decimal numbers and associated units of measurement in the healthcare workplace, in a manner that avoids confusion;

• understand the concepts of discrete and continuous variables and the best types of graphs used to represent these data;

• analyse, construct and extract information from grap
Author(s): The Open University

This sample of S110 material is taken from Module 2, entitled Using numbers and handling data. As you read the material, bear in mind that it is taken from a work-based course, designed for those who are employed in the health services, perhaps as a paramedic or as operating theatre staff. If you were a student on the course, you would have an OU tutor to help you, plus a work-based mentor supplied by the employer â€“ normally the NHS. The aim is to use the workplace as a teaching aren
Author(s): The Open University

The content acknowledged below is Proprietary (see terms and conditions). This content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence

Grateful acknowledgement is made to the following sources for permission to reproduce material in this unit:

## Author(s): The Open UniversityLicense informationRelated contentExcept for third party materials and/or otherwise stated (see terms and conditions) the content in OpenLearn is released for use under the terms of the Creative Commons Attribution-NonCommercial-Share

Now you have completed this unit, try the following questions to test your understanding of this material.

## Question 19

Most of the usable water is derived from the 1.1 Ã— 105 km3 that falls over the land surface each year as rain, snow, sleet or hail. The collective term for all of these sources of water is precipitation. At this point, you will consider the size of the drops of water that make up clouds or rain (Figure 5).

Author(s): The Open University

By the end of this unit you should be able to:

• recognise definitions and applications of each of the terms printed in bold in the text;

• understand and apply basic grammatical terminology;

• describe briefly the different types of sounds used in speech in both acoustic and articulatory terms;

• outline the key features of human language as compared to the vocalisations of other species;

• describe the complex psychologi
Author(s): The Open University

The document attached below includes the seventh section of Mountain building in Scotland. In this section, you will find the following subsections:

• 7.1 Introduction

• 7.2 Mid-Ordovician to Silurian sedimentation in the Midland Valley Terrane

• 7.2.1 Ordivician sedimentation

• 7.2.2 Silurian sedimentiation

• 7.2.3 Summary of Section 7.2

• 7
Author(s): The Open University

Some findings indicate that, for moderate loudness levels, humans can detect a frequency change of about 1 to 3 Hz for frequencies up to about 1000 Hz. Figure 37 shows a plot of the smallest frequency difference for which two tones can be discriminated for a number of reference tones. You can see from the figure that up to about 1000 Hz, the D
Author(s): The Open University

## Activity 14

What is the condition that results from vitamin C deficiency and what are its symptoms?

You will probably remember from the start of this
Author(s): The Open University

Vitamin B12 is yet another group of compounds, this time with an atom of the metal called cobalt (present in only trace quantities in the body) in their structure, hence the alternative name â€˜cobalaminâ€™. Vitamin B12 works alongside folate and if levels of it are low, folate deficiency symptoms occur too. It is stored in the liver and in general the body does not appear to need a regular intake. Many people have enough B12 stored in their liver to last for
Author(s): The Open University

Vitamin B, often called the vitamin B complex, consists of a whole range of different compounds, some of which have similar functions and work together. However, unlike the families of compounds forming vitamins E and K, the B vitamins are sufficiently different from one another to be given individual names or numbers, and to be listed separately on many food labels. Except for vitamin B12, the body can only store limited amounts of B vitamins and because they are all water-soluble
Author(s): The Open University

The full complement of 46 chromosomes in the human genome, the diploid number, is restored at fertilization. As Figure 3.1 shows, all the somatic cells and cells in the testes and ovaries arise from the same fertilized egg by the process of mitosis; the cells all contain copies of the same genetic material (with some exceptions).

Author(s): The Open University

When discussing the Meissner effect in Subsection 2.3, we argued qualitatively that a material that just had the property of zero resistance â€“ a perfect conductor rather than a superconductor â€“ would maintain a constant magnetic field in its interior, and would not expel any field that was present when the material became superconducting. We shall now show how that conclusion follows from an application of Maxwell's equations to a perfect conductor. We can then see what additional assumpt
Author(s): The Open University

A number of ingredients are essential for a satisfactory dissertation:

• a thesis, i.e. one coherent overriding â€˜storyâ€™ or argument

• situation in existing knowledge, i.e. a critical review of prior research which motivates and justifies the research question

• contribution of something new

• appropriate voice and argument, i.e. the provision of clear and explicit evidence, substantiation, and chain of in
Author(s): The Open University