Auniform thin rod of length 0.8390.839 m is hung from a horizontal nail passing through a small hole in the rod located 0.0310.031 m from the rod's end. when the rod is set swinging about the nail at small amplitude, what is the period of oscillation?

You want to move a heavy box with mass 30.0 kg across a carpeted floor. you pull hard on one of the edges of the box at an angle 30∘ above the horizontal with a force of magnitude 240 n, causing the box to move horizontally. the force of friction between the moving box and the floor has magnitude 41.5 n . what is the box's acceleration just after it begins to move