Blocks A, B, and C have weights of 50 lb, 25 lb, and 15 lb, respectively. Determine the smallest horizontal force P that will cause impending motion. The coefficient of static friction between A and B is µ's = 0.3 , between B and C, µ's = 0.4 and between block C and the ground, m's = 0.35
![1375_19f05e13-b309-4114-92b3-f8e6b5eb2e3a.png](https://secure.tutorsglobe.com/CMSImages/1375_19f05e13-b309-4114-92b3-f8e6b5eb2e3a.png)