Final answer:
To determine the reactions at points A and B when P=15 kips, we can draw a free-body diagram of the structure and consider its equilibrium. The reaction at point A is 15 kips, and the reaction at point B is 0 kips.
Step-by-step explanation:
To determine the reactions at points A and B, we need to consider the equilibrium of the structure. Assuming point P is the only external force acting on the system, we can draw a free-body diagram for the structure. Since the weight of the beam is neglected, the only forces acting on the beam are the reactions at A and B.
Let's assume that the reaction at point A is represented by RA and the reaction at point B is represented by RB. Since the structure is in equilibrium, the vertical and horizontal components of the reactions must balance each other.
Considering the vertical equilibrium, RA + RB = 15 kips (P).
Considering the horizontal equilibrium, RB * distance from P to B = 0. This means RB = 0, as there is no horizontal external force acting on the system.
Therefore, the reaction at point A (RA) is 15 kips, and the reaction at point B (RB) is 0 kips.