3. A 12 ft, 20 lb seesaw is balanced by a little girl (60 lb) and her father (180 lb) at opposite ends as shown below. How far from the seesaw's center of mass must the fulcrum be placed? 60lb 201b 12ft K 180lb

6. A 1.5 m long board with a mass of 4.2 kg sits on top of a 3.0 m long board with mass of 1.5 kg that is balanced on a pivot, as shown in Figure. What is the distance d? d Figure 1

A rod with a length L = 1.0 m long and a mass of 6.0 kg is pivoted around its center. A force of magnitude F = 5.0 N and angle 30° is applied at one end of the rod. A second force of magnitude F/2 is applied 0.25 m from the pivot at an angle of 53° as shown below. F 30⁰ m 53⁰ -pivot F/2 L/2 What is the magnitude of the angular acceleration due to the applied forces? L/4

A 32.0 kg child sits on one end of a long uniform beam having a mass of 18.0 kg, and a 40.0 kg child sits on the other end. The beam balances when a fulcrum is placed below the beam a distance 1.20 m from the 32.0 kg child. How long is the beam?  A. 1.93 m  B. 2.20 m  C. 2.07 m  D. 1.97 m  E. 2.12 m

8.

13. Freddy who weights 20kg, sits on one side of the seesaw which is 3.5m away from the center. His father sits on the other side and balances the seesaw. If his Father weights 70kg, how far away from the center is he sitting? 14. A Steel wire 3 ft long and a copper wire 2 ft long each 0.20in? in cross section, are fastened together end to end and are then subjected to a Tension of 200lbs. Calculate the elongation of each wire if the young's modulus of steel is 29x10 and 19x10 for copper.. 15. What is the absolute pressure at the bottom of a 10m water tank?