In physics, you must rely on imagination even more, but it is not too different from imagining the working of enzymes. If you view science as a mere collection of facts and equations to memorize, you will find it frustrating. Alternatively, if you approach science looking for new concepts, themes and a new worldview, then your efforts will be better rewarded. The reading comprehension portion of the MCAT is 85 minutes long and consists of about 9 passages, each about 500 words long and each with about 7 questions. The subject matter of a passage can be almost anything, but the most common themes are politics, history, culture, and science.
Most people find the passages difficult because the subject matter is dry and unfamiliar.
Obscure subject matter is chosen so that your reading comprehension will be tested, not your knowledge of a particular subject. Also the more esoteric the subject the more likely everyone taking the test will be on an even playing field. However, because the material must still be accessible to laymen, you won't find any tracts on subtle issues of philosophy or abstract mathematics. The passages use a formal, compact style. They are typically taken from articles in academic journals, but they are rarely reprinted verbatim.