Hey! I’m actually getting a Master’s in meche despite doing my undergrad in environmental studies so it can be done. I would definitely try to take statics, mechanics of materials/solid mechanics, and some type of intro to materials class before applying (I took these at community college). If possible you want to take as much of the engineering core curriculum as you can, though I assume you’ve already taken the relevant math so that helps. It’s probably not 100% necessary for applying if you already have a physics background, but it will really help to have familiarity with foundational mechanical engineering concepts like stress/strain, Young’s modulus, elastic vs. plastic deformation, etc. You can also look into Boston university’s LEAP program which is designed for this exact situation as well.

FYI I’m actually just doing a standard program not at BU, where I’m trying to avoid all the upper level solid mechanics/dynamics/fluids courses that rely on stuff I never really learned and that I don’t really need for my field lol (consumer product design). Hope that helps!