A ladder is an arrangement used for climbing on the walls It essentially consists of two long uprights of wood or iron and connected by a number of cross bars. These cross bars are called rungs and provide steps for climbing. Fig. shows a ladder AB with its end A resting on the ground and end B leaning against a wall. The ladder is acted upon by the following set of forces:
(1) Weight W acting downwards at its mid point.
(2) Normal reaction Rh and friction force Fh = µRh at the end B leaning against the wall. Since the ladder has a tendency to slip downwards, the friction force will be acting upwards. If the wall is smooth (µ = 0), the friction force will be zero.
(3) Normal reaction Ra and friction force Fa =µRa at the end A resting on the floor. Since the ladder, upon slipping, tends to move away from the wall, the direction of friction force will be towards the wall. Applying equilibrium conditions, the algebraic sum of the horizontal and vertical component of forces would be zero.
Problems on Equilibrium of The Body on Ladder.
