Physics 1 06 : Mechanics Lecture 07. Wenda Cao NJIT Physics Department. Static Equilibrium. Equilibrium and static equilibrium Static equilibrium conditions Net external force must equal zero Net external torque must equal zero Center of gravity Solving static equilibrium problems.
A) Find the magnitude of the upward force n exerted by the support on the board.
B) Find where the father should sit to balance the system at rest.
Rotation axis O
Rotation axis P