Question: To stay in practice, the Los Angeles Dodges pitcher Clayton Kershaw always throws globs of putty shaped liked baseballs to open doors. He keeps all the doors around his house unlatched. A baseball weighs about 150 g and Clayton throws the globs at 30 m/s. His doors are 1 m wide and 15 kg.
Part A: Assuming he always hits the edge of the door farthest from the hinge, how long does it take the door to open fully (90 degrees) (Assume the door acts like a rod rotating around it's hinge (I=1/2ml2).
I would really appreciate some help.