A 2-m uniform strut is pivoted at P. The strut is kept horizontal by means of a 3-m cable attached to the strut at Q and anchored in the wall at S. The weight of the strut is 250 N. A 300 N weight is suspended from Q.

1. The tension in the cable in SI units is:
A) below 510         B) 530               C) 550               D) 570           E) above 590

2. The horizontal force the pivot at P exerts on the strut in SI units is closest to:
A) 300                    B) 330                  C) 350             D) 380           E) 400

3. The vertical force the pivot at P exerts on the strut in SI units is closest to:
A) 95                      B) 105                  C) 115             D) 125           E) 135
 

Solutions

1.   SF_y = 0        - 300 - 250 + P_V + TsinQ = 0

2.   SF_x = 0        P_H - TcosQ = 0

3.   St = 0          -250 - 300.2 + 2TsinQ = 0

 1.   T = 570  D                                       2.   P_H = 380   D                                      3.  P_V = 125   D