# Need Help with a Tension problem

#### bobomajojo

A kind daddy is pushing his little girl on a swing in the park. One fun thing to do is to hold her in equilibrium for a moment before releasing her so she can swing back. the vector sum of daddy's force, the little girls weight, and the force of teh two chains of the swing is then zero.

Given: the little girl has a weight of 200n and the chains of the swing make an angle of 25 degrees to the vertical.

Find a) what is the combined tension in the two chains.
Find b) with what force must daddy push horizontally to hold his little girl in equilibrium?

#### HallsofIvy

The tension on the two chains is the component of force perpendicular to the circular trajectory of the child. That is the sum of the "centrifugal force" and the weight of the girl. The "centrifugal force" depends upon how fast the swing is moving. The weight vector is always vertical but the components perpendicular to and parallel to the circular trajectory depend upon the angle to the vertical the swing makes.

1 person

#### oz93666

The tension on the two chains is the component of force perpendicular to the circular trajectory of the child. That is the sum of the "centrifugal force" and the weight of the girl. The "centrifugal force" depends upon how fast the swing is moving. .
I think you've misread the question , Ivy ...

There is no movement , no centrifugal force.

Question b) is worded rather strangely , since daddy is pulling not pushing , so this answer will have a negative sign in front .

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