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Physics question HELP !!

A uniform beam of weight 230N & a length of 10m rests horizontally on the tops of 2 brick walls, 8.5m apart such that a length of 1.0m projects beyond one wall and 0.5m projects beyond the other wall.

a) Calculate the support force of each wall on the beam
b) the force of the beam on each wall

How do i work out B I dont need the answer to A (which btw is 121.8 and 108.2 (4 s.f))
Since the system is not accelerating, resultant force must be 0. This means that each force is balanced by an opposite force with the same magnitude. The force of the beam on the wall is the same as the force of the wall on the beam.
Reply 2
Original post by lizardlizard
Since the system is not accelerating, resultant force must be 0. This means that each force is balanced by an opposite force with the same magnitude. The force of the beam on the wall is the same as the force of the wall on the beam.


So the force of the beam on each wall is just the same as the moment for each beam?
Not the same as the moment, the same as the force. Essentially the same as the answers you got for part a), but in the opposite direction.

If the forces were any different, the beam would start flying up off the walls or down through the walls - obviously neither of those things are going to happen.
Reply 4
Original post by lizardlizard
Not the same as the moment, the same as the force. Essentially the same as the answers you got for part a), but in the opposite direction.

If the forces were any different, the beam would start flying up off the walls or down through the walls - obviously neither of those things are going to happen.


ik this sounds really dumb so does that mean that basically i would just write the answer to part A but as a negative, if not how/what would i write?
Reply 5
A uniform beam of weight 230 N and of length 10m rests horizontally on the tops of two brick walls 8.5 m apart, such that a length of 1.0m projects beyond one wall and 0.5 m projects beyond the other wall (Fig 5).
1.0 m
8.5 m
0.5 m
Fig 5
Calculate:
a the support force of each wall on the beam,
b the force of the beam on each wall.

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