But physics is also an extremely practical subject. It underpins most of today's technologies. That is probably why extensive surveys by the Institute of Physics have shown that physicists are welcomed by a wider group of professions than people from any other discipline. Moreover, physicists who choose not to use their specialist knowledge are much in demand in management, financial services, the media, information services and other sectors where numeracy and an enquiring and analytical mind are an asset. Physics is good preparation for most careers in today's world.
It is surprising therefore that there is a considerable shortage of applicants to study physics. Dr A Clarke, a senior lecturer in the Physics Department of Leeds University, says that: "One reason why physics is not so popular is that, unlike chemistry, we don't have a well-defined vocational end- point. We don't have anything like the pharmaceutical industry. Physicists tend to go into such a broad spectrum of jobs.
"We did a survey of second-year physics students and found that over half still had no clear idea of what they were going to do at the end of their course. I think physics as a subject attracts those students who love the subject for the sake of the subject rather than have any clear idea of going on to do something which is physics related." However, physicists are not unusual in this respect. The annual surveys of final year students by MORI showed that half of all graduates had not chosen their career field even half way through their final year.
Another possible reason for the shortage of applicants is the level of mathematics needed. Dr Clarke says: "Of all the science subjects, physics is the most demanding from a mathematical point of view. Sadly, young people don't seem to be so well prepared in mathematics. We have to take people in the A-level grade C area and run remedial maths and remedial physics for people coming into our courses."
Caroline Harman from Hull, who has an A-level grade B in maths, chose to read physics and astronomy at University College London (UCL). She says that she chose these subjects because her physics teacher at school "made it sound very interesting. But I also thought it would be practical because it opens up so many different career options and it's a respected degree. I was also quite interested in astronomy.
"The course was fine. It was a bit overwhelming at first, but everyone helps. The most difficult part was the maths content. No one actually tells you how much maths there is. When you start off at UCL they give you all the interesting courses on practical physics, lasers and astronomy, so after the first term you get really excited. Then round about the Christmas they throw in the mechanics, optics and those sort of subjects. Then towards the end it gets really interesting again. They do it to keep you interested."
She advises would-be physics students to choose their course very carefully. "Although physics courses sound very similar, there is physics, physics and astronomy, astrophysics, medical physics and so on. At first no one explains the difference to you. You have to think of what you want to do in the long run and then work back.
"Thinking about it now, I wish I'd done medical physics, but no one explained anything to me. You need to ring up the course tutors and get them to explain everything. The different universities have different courses. You have to choose your university very carefully."
She says the research grading given to a physics department is important. A good grading "attracts stronger PhD students, and they're often our first contact in getting help with problems". And, she adds, "it attracts higher quality lecturers as well".
She advises would-be students to visit the departments they are thinking of applying to. She visited five, finally choosing UCL because, "I just seem to get on better with the people here than anywhere else. It also has a theatre, a strong union, lots of extra activities and I like its centrality. If you want you can even get to the British Museum in your lunch hour."
In career terms she says: "When you do a physics degree you become a student member of the Institute of Physics. They send you information about jobs, PhDs and other things.
"Gradually I decided I didn't want to do a PhD so at the moment I'm a bit confused. I'll take a year out, then I think I'll go back and do a masters in medical physics. In medical physics you can do things every day that make a difference."
Physics is a very broad discipline, so most courses concentrate on the fundamental principles before moving on to more advanced theories and practical work.
As a result, there are fewer opportunities to specialise before your final year than in many other subjects. But then you might choose to specialise in a huge range of topics as varied as atomic physics, astrophysics, radiation physics, acoustics, optics, geophysics, or medical physics.
There are also a variety of combined courses in which you study physics with another science such as chemistry or geology, or even with a non- science subject such as business studies, a modern language, philosophy, music, psychology, or even Scottish history.
Finally, some universities offer four-year MSc or MPhys courses, the final year have a core of advanced physics, an optional element, and a project component which may be replaced by industrial training.
All 720 physics courses are listed in Physical Science Courses 2000, published by Trotman in association with UCAS, at pounds 14.99 (tel 0870 900 2665)