A72.0-kg person pushes on a small doorknob with a force of 5.00 n perpendicular to the surface of the door. the doorknob is located 0.800 m from axis of the frictionless hinges of the door. the door begins to rotate with an angular acceleration of 2.00 rad/s2. what is the moment of inertia of the door about the hinges?

You are your friend move a new refrigerator into his kitchen. you apply a horizontal force of 252 n in the negative x direction to try and move the 56 kg refrigerator. the coefficient of static friction is 0.61. (a) how much static frictional force does the floor exert on the refrigerator? give both magnitude (in n) and direction. magnitude n direction (b) what maximum force (in n) do you need to apply before the refrigerator starts to move?