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# Reactions calculation

Dear Friends, i have to face a problem in calculation of reactions from these equations

R1 + R2 + R3 = 40

0.625R1 + 0.275R2 = 9

0.275R3 - 0.35R1 = 2

0.625R3 + 0.35R2 = 16

0.175R2 + 0.45R3 - 0.175R1 = 9

Please calculate R1, R2, R3 and tell me i m very thankful to you.

R1 + R2 + R3 = 40

0.625R1 + 0.275R2 = 9

0.275R3 - 0.35R1 = 2

0.625R3 + 0.35R2 = 16

0.175R2 + 0.45R3 - 0.175R1 = 9

Please calculate R1, R2, R3 and tell me i m very thankful to you.

Mention the procedure if you feel it easy!!!!

There seems to be a redundancy in this. Only three independent equations are required for three variables.

There are four here.

There are four here.

To much of data to solve the equations I would say there is some minor error which makes it not feasible for solving these equations

But sir we are here at upper position because we have more equations then no. of unknowns so what is the reason that corresponding reactions are indeterminate.bioramaniThere seems to be a redundancy in this. Only three independent equations are required for three variables.

There are four here.

In this problem the data given has a little error and so makes solving not possible you seeAmmar AzizBut sir we are here at upper position because we have more equations then no. of unknowns so what is the reason that corresponding reactions are indeterminate.

error of what type. i assure you that the data is correct. but if you have objection then what is the criteria on which we decide that whether the reactions are indeterminate or not.jeffrey samuelIn this problem the data given has a little error and so makes solving not possible you see

What are these reactions that you are referring to? Reaction to a force? Are these experimental equations? If these are mechanical forces and if some non linear thing like thixotropic substances are involved forces can be indeterminate.Ammar Azizerror of what type. i assure you that the data is correct. but if you have objection then what is the criteria on which we decide that whether the reactions are indeterminate or not.

is this problem from finite element methods

actually these equations are derived from the analysis of a beam hanging horizontally with three springs. at the same time we apply two loads on two loading hangers attached with the above mentioned beam. these equations are derived by considering the equilibrium condition and applying the "sum of moments around a particular point due to all forces is zero" principle. actually the reactions which i mention in my post are the reaction forces to applied loads. and it is the springs which react to the applied load by generating upward forces in beam. now i think situation is clear.bioramaniWhat are these reactions that you are referring to? Reaction to a force? Are these experimental equations? If these are mechanical forces and if some non linear thing like thixotropic substances are involved forces can be indeterminate.

it is a very simple case but i wonder what factors resist in calculation of reactions

That part is clear now. Thanks. However, how were these four equations generated? There cannot be four independent equations in three variables.

There are

**FIVE**equations not four. Are these simultaneously applicable? Only simultaneous equations can be evaluated. If these are based on operations under different conditions, then there may be no valid solution.