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In this problem on the topic of analysis of structures, we are shown two trusses and we want to determine the zero force members in each of these trusses.
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We are also given certain loadings.
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Now we have three body diagrams for trust a and trust b.
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So let's first look at trust a.
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Note that the reaction at f is vertical and so fx is equal to zero.
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Now, if we look at the different joints, at joint g, if we take the sum of the forces, the vertical direction, this must equal to zero.
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And so this implies that f, d, g is equal to zero.
01:01
That's our first zero force member.
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At joint d, we should have the sum, of all the forces again equal to zero.
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Remember we have equilibrium.
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And we take diagonally to the right and to the top to be positive.
01:26
And the sum of the forces must be again zero, which means that f dv is equal to zero...