10 kg 20 kg 15 kg The picture shows a board in equilibrium. You can see only three objects from the four sitting on the board. The first object (10 kg) is located 50 cm from the pivot. The second object is located 30 cm from the pivot. The third object is located again 20 cm from the pivot. Find the mass of the forth (hidden) object if it is located 70 cm from the pivot.

A 5.0 kg fire extinguisher and a 10 kg trashcan are placed on a teeter-totter, each 1.0 m from the fulcrum (center) as shown.  They of course do not balance, so the teeter-totter is not level.  How many meters (on the right) from the fulcrum should the trash can be placed to so that it balances with the fire extinguisher (which you do not move)?

Please help!

A meter stick is hanging from the ceiling at the 50 cm marker, perfectly in balance.. A 10 kg mass is tied to the meter stick at the 70 cm marker. A 10 kg mass is tied to the meter stick at the 80 cm marker. Where should a 20 kg mass be placed to maintain equilibrium? 25 cm 10 cm 20 cm 35 cm

The center of mass of a person may be determined by an arrangement such as the one shown in the figure below. A light plank rests on two scales separated by a distance of d = 1.80 m and reading Fg1 = 470 N and  Fg2 = 260 N. Determine the distance of the girl's center of mass from her feet.

A block of mass m= 5.00 kg is reased from point A and slides dows the frictionless track shown in the figure. calculate the speed of the block at piont B and C. g= 9.8m/s2

The uniform seesaw shown below is balanced on a fulcrum located d1 = 3.5m from the left end. The bigger boy on the left end has a mass m1 =75 kg. The smaller boy on the right end has a mass of m2 = 55 kg and is a distance d2 = 4.5 m from the fulcrum. The mass of the board is mb.    Draw all forces acting on the seesaw board showing their directions and locations. Where would you draw the weight of the board? Identify and show the direction of rotations caused by the torques provided by all forces about the fulcrum. If the seesaw is in static equilibrium, write down the two conditions of static equilibrium symbolically using the forces and distances in the figure. Solve for the mass of the board. Calculate the force of fulcrum on the board.

ASAP

In the figure, a nonuniform bar is suspended at rest in a horizontal position by two massless cords as shown in the figure here. One cord makes the angle 0 = 29.5° with the vertical; the other makes the angle p = 60.5° with the vertical. If the length L of the bar is 6.8 m, compute the distance x from the left end of the bar to its center of mass. com X = i

A rider of mass 77.0-kg sits 1.60 meters left of the pivot point.  A different rider sits 3.3 meters to the right of the pivot point. If the see-saw is in equilibrium, what is the rider on the right's mass? The mass of the see-saw is 18.9-kg  Give your answer in kilograms to 3  significant figures (1 decimal place).