Well, my final question before the big test, but this is messing me up in various assignment questions (rrrr). How do you find the magnitude of an object when friction is negligible? What is the actual definition of magnitude? I didn't take Physics 11, and this isn't in my notes or textbook. Help is very much appreciated!

What do you mean by the magnitude of an object? It makes sense to talk about the magnitude of a vector, or the entirely different magnitude (logarithmic brightness scale) of a star, but not that of a simple massive object.

Don't worry about the concept of magnitude of an object. It doesn't exist.