As a math and physics tutor, I am well aware of how students tend to see the subjects they study as distinct from each other. “Math is in first block with Mr. Smith. I need my green text book. The first test is next Thursday. Physics is in second block with Ms. Jones. I need the book by Giancoli. The first mid-term will be the day after Thanksgiving.” Their perception very naturally reflects their most relevant concerns.
In the world beyond high school, these and other disciplines have huge areas of overlap. As a young astronomy undergrad I was surprised to find that most of the major research papers on planetary science were published in the Journal of Geophysical Research, rather than in periodicals like the The Astronomical Journal. A few years later I discovered the extremely interdisciplinary nature of oceanography with its physical, chemical, and biological branches. Climate science, which gets a great deal of publicity these days, brings together almost every “outdoor” branch and sub-branch of science that I can think of: oceanography, glaciology, meteorology, space physics, geophysics, geology, zoology, botany, etc.
Drawing heavily upon physics and chemistry, materials science is an extremely important multi-disciplinary area of research. Many people have heard some of the buzz words like nanotechnology, composite materials, and carbon fibre nano-tubes that have emerged from it but materials science in general does not get the attention it deserves. This article from ScienceNews for Kids helps to remedy that with a story about a structure made from small X-shaped blocks that can support much more weight than might ordinarily be expected. It also provides a nice glossary of related terms.