How are vector spaces, subspaces, and spans useful in applications to physics?

I am a physics and math major currently taking linear algebra. I find vector spaces and subspaces of vector spaces to be quite abstract and cannot see any immediate application to physics like I do with my calculus class. Are there many? I would love to know of some applications of vector spaces to physics. Thanks in advance.|||http://www.physics.sfsu.edu/~bland/cours…