Question

Two children sit on a 10 kg seesaw. The first is 40 kg, and the second is 30 kg. The first sits 0.5 meters from the seesaw pivot. If the second child were sitting at the same distance from the pivot as the first child, what would the angular acceleration of the system be? (Hint: you must first find the total moment of inertia of the system, which you can find by adding up all the moments of inertia of the parts of the system)

Answer 1

First child of mass is sitting at to the left of seesaw, and second child of mass is sitting at to the right of seesaw.

Mass of seesaw is

Length of seesaw ( distance between the two children, assuming the two children are at two ends of seesaw )

Moment of inertia of system  

Torque about the pivot is

Angular acceleration of system is