3. A 15-kg uniform beam is 3.0 m long and is pivoted 1.0 m from the left end. A 35 kg child sits on the left end of the beam 0.60 m from the pivot. How far from the pivot must a 20 kg child sit in order for the beam to be in equilibrium?

5. Torque. A square metal plate 0.180 m on each side is pivoted about an axis through point 0 at its center and perpendicular to the plate. Calculate the net torque about this axis due to the three forces shown in the figure if the magnitudes of the forces are F₁ = 18.0N, F2 = 26.0N, and F3 = 14.0N. The plate and all forces are in the plane of the page 0.180 m 0.180 m 8. 45° F3 F1

2. A boy weighting 600 N sits 2.5 m from the center of the see-saw. If his friend weighs 750 N, how far from the center should his friend sit so that the see-saw balances?

The foot of a ladder rests against a wall and its top is held by a tie rope, as shown. The ladder weighs 100 N, and its center of gravity is 0.4 of its length from the foot. A 150 N child hangs from a rung that is 0.2 of the length from the top. Determine the tension in the tie rope. Tie rope 10-16: won megd 150N 150 N 37° 100 N 0.4L

A 2.00-m-long, 500 kg steel uniform beam extends horizontally from the point where it has been bolted to the framework of a new building under construction. A 70 kg construction worker stands at the far end of the beam. What is the magnitude of the torque about the bolt due to the worker and the weight of the beam?

In exercise physiology studies, it is sometimes important to determine the location of a person's center of gravity. This can be done with the arrangement shown in the figure below. A woman of length 2.00 m lies on top of a horizontal plank so that her head is near the left end of the plank and her feet are near the right end. Each end of the plank is supported by a scale. The scale on the left is labeled Fg1, and reads a slightly larger value than the scale on the right, which is labeled Fg2.     A light plank rests on two scales that read Fg1 = 380 N and Fg2 = 260 N. The scales are separated by a distance of 2.00 m. How far from the woman's feet is her center of gravity? ???? m

The figure shows a 4.20-kg, 1.80-m-long rod hinged to a vertical wall and supported by a thin wire. The wire and rod each make angles of 45° with the vertical. When a 10.0-kg block is suspended from the midpoint of the rod, the tension T in the supporting wire is 49.3 N. The wire will break when the tension exceeds 75.0 N. 45° 45° T 10kg Tipler & Mosca, Physics for Scientists and Engineers, 6e © 2008 W.H. Freeman and Company What is the maximum distance dmax from the hinge from which the block can be suspended? dmax 0.871 Incorrect m

3. A large board L 6.00 m and m 25.0 kg is laying so that d = 1.00 m of the board hangs off the roof of a building. A contractor puts his toolbox on the end of the board as shown. What is the greatest mass the toolbox can have and not cause the board to flip up and slide off the roof?

A homeowner is trying to move a stubborn rock from his yard. By using a a metal rod as a lever arm and a fulcrum (or pivot point) the homeowner will have a better chance of moving the rock. The homeowner places the fulcrum a distance ?=0.266 m from the rock, which has a mass of 325 kg, and fits one end of the rod under the rock's center of weight.

Two children of mass 21 kg and 26 kg sit balanced on a seesaw with the pivot point located at the center of the seesaw. If the children are separated by a distance of 2 m, at what distance from the pivot point is the small child sitting in order to maintain the balance? m