For the block-and-wedge system shown in Figure 6-17, calculate the force P required to i...

For the block-and-wedge system shown in Figure 6-17, calculate the force P required to initiate upward motion of the block. The block supports a load of 7001b, the slope angle of the wedge is 9°, and the coefficient of static friction on the two sur-faces of the wedge is 0.25. The vertical surface (C-C) is friction-less. Compare the result with Example 6-7.

Figure 6-17

Example 6-7

The block shown in Figure 6-19 supports a load W of 700 lb and is to be raised by forcing a wedge under it. The coefficient of friction on each of the three contact surfaces is 0.25. Calculate the force P required to start the wedge in motion under the block. Neglect the weights of the block and the wedge.