Conceptual Dynamics - Independent Learning

Rotation about a Fixed Axis - Example Problem 6.6-4

 

The pendulum shown consists of a 10-lb sphere (r = 2 in) and a 10-lb slender rod (L = 1.5 ft). Determine the reaction force at the support pin O as the pendulum passes the horizontal position with an angular velocity of ω = 6 rad/s.

 

 

Given:
  • Wsphere = 10 lb
  • Wrod = 10 lb
  • r = 2 in
  • L = 1.5 ft
  • ω = 6 rad/s

 

Find: O

 

Video solution:

 

The following video walks you through the solution to this problem. It is suggested that you try solving the problem first and then, if you have difficulties with the solution, watch the video for help.

 

 

Interactive solution:

 

Draw a free-body diagram of the pendulum. Think about which coordinate system will simplify the analysis. Click on the figure to see the FBD.

 

Which point should we sum the moments about?