The UK driving theory test is split into two sepaprtae parts, both of which have to be passed on the same occasion. The first part involves the candiadate answering 50 multichoice questions which are shown on a computer screen. The time allowed for the question part of the UK driving theory test is 57 minutes. Some questions have more than one answer and it is required that the candidate identify all correct answers for that question. The pass mark score for the theory test is 86%.
On completion of the questions, the candidate is required to watch 14 clips of video film. The DSA are in the process of transitioning from real life video to computer generated video images. The clips of film usually last for around 25 seconds and each contain one or two hazards taht you will score for. The hazards that you need to identify are the ones that require you to taske avoiding action - for instance a pedestrian stepping out into the road in fron tof you or a lorry emerging from a side road and requiring you to slow down. The sooner you identify each hazard, the higher your score will be. The pass mark is 44 out of a possible 75 marks.
The overall pass rate for the UK driving theory test is around 60% overall. The majority of people who fail do so because they are insufficiently prepared for the test - either they have not done enough theory test revision for the questions, or they do not fully understand how the hazard perception test works.
There are numerous resources for the UK driving theory test including Driving Test Success from Focus Multimedia.