There are a lot of factors that determine the appropriate length of a quality answer. What constitutes a good answer depends on the type of subject, the requirements of a particular question, the candidates verbosity (or the lack thereof), as well as the scope and depth of one's approach.

Time is the only constant and so I believe that the length of your answer should primarily be dictated be the amount of time that you have. For CSS, you'll have about 40 minutes for each 20 mark question. After brainstorming and writing an outline (which I highly recommend) you'll be left with about 30 minutes for each question. Now, you'll be expected to answer the question directly, keeping in mind that you'll also have to incorporate the answers to subsidiary questions that follow the main question. CSS examiners divide questions into 2 or 3 parts but they do not mention how these parts are weighed in terms of marking therefore you're expected to make a judgement call and present a balanced answer to all parts within the given time. If you spend 10 minutes for brainstorming and organizing your thoughts, your only job in the remaining time would be to expand on those ideas. You won't have to pause and come up with new thoughts midway through your answer. Every person has a unique writing style and speed; on average, I was able to write 500-550 words in 30 minutes. 7 words per line and 18 lines per page, my answers were mostly 4 pages long.

You have to keep in mind that some answers will include diagrams, flowcharts and tables. Your answers to such questions will vary in length considerably, depending on what information you chose to include.

During the exam you'll find that 30 minutes are not enough to give a comprehensive answer to any question posed by the examiner. You'll be judged not only by the quality of your answer but also by how you manage to fit in your answer(s) within the given time.

Your example: Define social research and steps taken in carrying it out?

The scope of this question is so broad that you can write for hours on end on this one question alone (if you've done your homework).

You begin by defining "Social Research" which should take no more than 3-4 lines. Then you differentiate between quantitative and qualitative social research. Mention reliability and validity. Then you go on and list various techniques that are employed in carrying out social research, such as surveys, questionnaires, interviews, regressions, case studies and experiments etc. You can have a paragraph for each method listing its definition as well as its merits and demerits. This should take a page and a half or so. Then you move on to specify steps in each one. There are several types of surveys and they all have different steps. Same is the case for interviews and experiments. Simply explaining steps for conducting experiments in 30 minutes will be a daunting task. From forming a hypothesis, to identifying dependent and independent variables, to choosing sample, to assigning control and experiment groups, to minipulating independent variable, to measuring changes, to analyzing results. You'll also be expected to identify and explain relevant concepts along the way (such as double-blind procedures, longitudinal studies) and their usefulness in conducting social research. In the end you're expected to ties up loose ends and go back to the bigger picture of social research.

The way I see it, it's not about how much you should write, it's about how much relevant stuff you can fit in within the given time.

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