## Would it be possible for somebody to explain how I can solve this problem?

The diagram shows a uniform horizontal beam of negligible mass, 5.0 m long, placed on two supports, one at each end. It has a 300 N weight placed 1.0 m from one end and a 500 N

weight placed 1.0 m from the other end. Both weights act vertically on the beam as shown in

the diagram.

What are the upward forces from the two supports acting on the beam?

340 N and 460 N

300 N and 500 N

240 N and 560 N

400 N and 400 N

360 N and 540 N

## Answer ( 1 )

Total weight = 300 + 500 = 800 N

Let F1 be support force at the left end of beam. F2 is the support force at the right of the beam. T he sum of the two forces is equal to the total weight.

F1 + F2 = 800 N

Let the pivot point be at left end of the beam. The two weights will produce clockwise torque. The support force at the right end of the beam will produce counter clockwise torque.

Total clockwise torque = 300 * 1 + 500 * 4 = 2,300 N * m

Counter clockwise torque = F2 * 45

F2 * 5 = 2,300

F2 = 460 N

460 + F1 = 800

F1 = 340 N