Personalized Ohm Mighty Physics Youth Long Sleeve T-Shirt. Ohm Mighty Physics with ohm mighty in coiled text inside a yellow burst. Tickle the funny bone of your favorite science geek with this design for birthdays, holidays, back to school and graduations for your favorite scientist youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)