Question

Help me please

Answer 1

@mathmate

Answer 2

@mathmate

Answer 3

@jacalneaila
Need to clarify a few things before starting to work on the problems.
1. Are these frames or trusses?
If they are frames, there should be hinges only at the supports, and the other \(joints \) should not have a black dot (meaning hinge) shown.
2. If they are trusses, I don't believe they are stable.
3. Also, please clarify the support condition at support A of the second frame, is it an ordinary hinge, or is the member BA resting on a roller (meaning the reaction is perpendicular to the tangent BA).
4. Or, is it a normal roller support with reaction vertically upwards?

Answer 4

its a frames

Answer 5

What about the support condition of the second frame at A?

Answer 6

Did you calculate the reactions?

Answer 7

For the first one, I have
Ray+Rfy=0,
Rax+Rfx+100=0
Substitute Rfy and Rfx into following (so system of 2 equations)
Ma: -100(9)-Rfx(4)+Rfy(12)=0
Mf: -100(5)-Rax(4)+Rfy(12)=0
Solving gives
Rax=0,Ray=-125/3,Rfx=-100,Rfy=125/3