A uniform bar of length 4.0m and 80kg rest with its upper end against a smooth vertical wall and and with its lower end on the rough surface to coefficient of friction 0.32.What is the maximum angle made with the horizontal to which the bar can be inclined without sliding?​

Astone is thrown with a speed v0 and returns to earth, as the drawing shows. ignore friction and air resistance, and consider the initial and final locations of the stone. which one of the following correctly describes the change δpe in the gravitational potential energy and the change δke in the kinetic energy of the stone as it moves from its initial to its final location? options a.δpe = 0 j and δke = 0 j b.δpe is positive and δke is negative c.δpe = 0 j and δke is positive d.δpe is negative and δke is positive e.δpe = 0 j and δke is negative