A seesaw has a mass of 30 kg, length of 3.0 m, and fulcrum beneath its midpoint. It is balanced when a 60 kg person sits on one end and a 75 kg person sits on the other end. Locate the center of mass of the seesaw. Where is the center of mass of a uniform see saw that is 3.0 m long and has a mass of 30 kg if two people of masses 60 kg and 75 kg sit on its ends?

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Two kids are playing on a seesaw on the school playground. The first kid (of mass 50 kg) sits 2 meters from the fulcrum. The other child (who has a mass of 70 kg) sits on the other side of the seesaw. How far away from the fulcrum does the second child need to sit in order to balance the seesaw? Assume that the seesaw itself is weightless. O 0.79 m O 1.43 m O 1.03 m O 2.24 m

A uniform, 20-kg, 8.0-m-long, wooden plank that is parallel to level ground is supported by two pivots: one pivot is at the extreme left end of the plank, and the other pivot is 3.0 m inward from the extreme right end of the plank. A 80-kg construction worker, who is initally standing on the extreme left end of the plank, begins to walk to the right. How far from the right end of the plank will the worker be located when the plank begins to tip? 4.0 m 4.0 m 5.0 m a. 4.50 m O b.5.00 m O c. 4.25 m d. 5.25 m O e. 4.75 m

Three children is trying to balance a uniformed seesaw. Boy A who has a mass of 20-kg is placed 3.5 meters away from the support on the one side of the seesaw.  Boy B who has a mass of 40-kg sits 2.5 meters away from the support on the opposite side of the seesaw. The seesaw is made up of a steel that is 10-kg and 10 meters long. Where should the girl whose mass is 25-kg place herself to balance the seesaw? Find the magnitude of the upward force exerted by the support on the steel.

A wood plank has a length of 4.2 m and a mass of 14.3 kg. The plank is balanced between two saw horses. One saw horse is positioned directly under one end of the plank, and the other is located a distance d1 = 3.2 m away. A child with a mass of 29 kg walks along the plank, as if it were a balance beam. What is the furthest distance d2 (in meters) from the end of the plank that the child can walk before the plank tips and falls? NOTE: When the plank starts to tip, one of the forces becomes zero.

The diagram above shows a 3.00 m long uniform beam. The left end of the beam is attached to a wall by a frictionless pivot. The beam is supported by a string that keeps the beam horizontal. The string makes an angle of 35.0° relative to vertical. The beam has a mass of 7.00 kg. A 2.00 kg mass is located at the end of the beam. A 6.00 kg mass is located 1.00 m from the 2.00 kg mass, as shown in the diagram. a.  What is the tension in the string? b.  What is the y-component of force applied to the beam by the pivot?

Bob and Anna sit on opposite ends of a uniform see-saw which is 12.0 m in length. The see-saw is balanced by a fulcrum which is located 4.00 m from Bob. Bob has a mass of 85.0 kg, and the see-saw itself has a mass of 100 kg. Anna’s mass is unknown. NOTE THAT THE FULCRUM IS NOT PLACED AT THE CENTER OF MASS OF THE SEE- SAW!!! a)   What is the net torque on the see-saw? Explain clearly and briefly how you know. b) Draw a properly labeled extended force diagram of the see-saw   c) Solve for Anna’s mass. Show your work clearly!

Scenario: A heavy kid and a light kid are at the two ends of a see-saw, modeled as a long thin rod with point masses at each end, pivoted at the middle. The see-saw is tilted from horizontal. See-saw end-to-end length: 4.5 meters See-saw mass: 15 kg Heavy kid's mass: 39 kg Light kid's mass: 25 kg Tilt angle: 14 degrees (a) What is the magnitude of the net torque on the see-saw due to gravity, in newton-meters? N m (b) What is the moment of inertia of the two-kid system about the pivot at the center of the see-saw? kg m2 (c) What is the magnitude of the see-saw's angular acceleration at this instant? rad/s?

In exercise physiology studies, it is sometimes important to determine the location of a person’s center of mass. This determination can be done with the arrangement as shown. A light plank rests on two scales, which read Fg1 = 380 N and Fg2 = 320 N. A distance of 1.65 m separates the scales. How far from the woman’s feet is her center of mass?