Question

A "teeter-totter" (or "see-saw" if you prefer) has a 50 lb child sitting at one end, 10 ft. from the center pivot point (fulcrum). How far from the center point should a 125 lb. adult sit in order to balance the teeter-totter?

a) 4 ft.

b) 10 ft.

c) 2.5 ft

d) 6.5 ft

Answer 1

To balance a teeter-totter, the adult should sit 4 feet from the pivot. This is found by equating the product of weight and distance from the pivot for both individuals and solving for the unknown distance.

Step-by-step explanation:

The question is related to the concept of torques and equilibrium in physics, specifically how to balance a teeter-totter (or see-saw).

To balance the teeter-totter with a 50 lb child sitting 10 ft. from the center pivot, the condition that must be satisfied is:

torque(child) = torque(adult)

Which translates into:

weight(child) × distance(child from pivot) = weight(adult) × distance(adult from pivot)

In this case:

50 lb × 10 ft = 125 lb × distance(adult from pivot)

Solving for the distance(adult from pivot), we get:

distance(adult from pivot) = (50 lb × 10 ft) / 125 lb = 4 ft.

Therefore, the correct option is a) 4 ft.