What is the difference in lever arms between two people on a seesaw?

[xlaserx7]

Two people of different weights are sitting on a seesaw. The seesaw is not rotating. How would the lever arm of the heavier person compare with the lever arm of the lighter person?

 

[mender]

If the seesaw is free to rotate, the length of the lever arms are inversely proportional to the weight of the people. In other words, if one person weighs twice as much, their side of the seesaw has to be half as long from their centre of gravity to the pivot of the seesaw as the other person's in order to remain balanced.

 

[thomate1]

The lever arm is the distance between the pivot point (fulcrum) and the point where the force is applied. In the case of a seesaw, the pivot point is the center of the seesaw and the force is applied by the weight of the person sitting on each end.

In this scenario, the lever arm of the heavier person would be longer than the lever arm of the lighter person. This is because the heavier person exerts a greater force on the seesaw due to their higher weight, resulting in a longer distance between the pivot point and the point where the force is applied.

This can be explained by the principle of torque, which states that the magnitude of a force is directly proportional to the distance from the pivot point. Therefore, the heavier person would have a greater torque than the lighter person, causing the seesaw to be balanced.

In summary, the lever arm of the heavier person would be longer than the lever arm of the lighter person on a seesaw, due to the difference in their weights and the resulting difference in the magnitude of their forces.