Suppose you are on a teeter-totter. Use the concept of net force to explain why one person goes up when the other person goes down. What needs to happen for the teeter-totter to be balanced?

The mystery behind the see-saw motion lies in force and genesis of counterforce.

Balanced Teeter totter can be achieved by placing equal masses or length adjustment (betwen pivot and mass) for varying mass.

Explanation:

Teeter totter is a wonderful manifestation of physics principles in crude form.

The working of Teeter totter can be explained as-

The whole set-up (Teeter totter) is balanced on a pivot or fulcrum. When either of its edges/sides is loaded, it moves down under the impact of its mass & gravity (force=m*gravity).  

Equal and opposite counterforce acts on the other end of the Teeter totter to balance the effect of the previously applied force. As a result of this, the other side is raised upwards in the air.

As a result of this the net force remains balanced on either side (considering similar masses are on both ends of the Teeter totter)

For a Teeter totter to be balanced there are two conditions-

dicrrdirrkdirckrrdrrk ; jhgfdsgrthyjkul; i'lkjhgfdskhjl; jhgdfs

heats surface water up