A3.00-m-long ladder, weighing 200 n, leans against a smooth vertical wall with its base on ahorizontal rough floor, a distance of 1.00 m away from the wall. the ladder is not completelyuniform, so its center of gravity is 1.20 m from its base. what force of friction must the floor exerton the base of the ladder to prevent the ladder from sliding down

Alinearly polarized electromagnetic wave has an average intensity of 196 w/m^2. this wave is directed towards two ideal polarizers (in real polarizers, transmission is also effected by reflection and absorption). polarizer a is oriented with its transmission axis at an angle of θ_1=20.8∘ with the incident electric field. polarizer b has its axis at an angle of θ_2=63.0∘ with the incident electric field. what is the average intensity of the wave after it passes through polarizer a? what is the average intensity of the wave after it passes through polarizer b? suppose that the two polarizers a and b are interchanged. what would the average intensity be after passing through both polarizers?