Engineering Statics

E-22


Blocks A and B weigh 100 lb and 180 lb respectively. Determine the magnitude of the largest instantaneous force P for which block A will start sliding down.

The FBD of the block A and wedge B are drawn.  Again, notice that forces 
acting on touching bodies are equal and opposite.
The force equation in the x direction is written for block A.
The equation is simplified.
The force equation in the y direction is written for block A.
The equation is simplified.