Can someone please help me with the following question on torque (specifically, I am confused how to take into account the mass of the plank)? A teeter totter is made of a uniform plank of mass 20kg and length 8m. A girl of mass 30kg is positioned at one end and a boy of mass 45kg is positioned at the opposite end. How far from the girl is the fulcrum of the teeter totter located when it is in balance?

Question

Can someone please help me with the following question on torque (specifically, I am confused how to take into account the mass of the plank)?  A teeter totter is made of a uniform plank of mass 20kg and length 8m.  A girl of mass 30kg is positioned at one end and a boy of mass 45kg is positioned at the opposite end.  How far from the girl is the fulcrum of the teeter totter located when it is in balance?

anonymous · Answer

Why use torque when you can use moments?

anonymous · Answer

|dw:1352922625600:dw|Treat the log as if its mass were concentrated at its centre