Force directions acting on
the misaligned firework


Several types of fireworks use two rockets to cause the fireworks to spin rapidly and rise up in the air. If the thrust from the two rockets is not aligned properly, the fireworks will move in a certain direction as well as spin. This direction can be determined from an equivalent force-couple system or force resultant.

What is known:

  • Each rocket has a thrust of T = 0.5 lb.
  • One of the engines is misaligned by α = 10°.
  • The necessary dimensions are shown.

  1. What is the equivalent force-couple system at point O?
  2. If one is possible, what is the force resultant?

  • Use a vector approach to determine the equivalent force and moment at point O.
  • Solve for the position of the force resultant, if one is possible.