Obey Gravity It's the Law Physics Earth Funny Pun T-ShirtMachine wash cold with like colors, dry low heat Obey Gravity It's The Law shirt is perfect for science majors, students, professors, astrophysicist, College and kids. Everyone will have a laugh when they see you wearing this Tee. Physics is the law and is universal anywhere you go! Obey Gravity It's The Law tee has a unique phrase that means a force that attracts a body toward the center of the earth, or toward any other physical body having mass.