Three boards, each 50 mm thick, are nailed together to form a beam that is subjected to a 1200-N vertical shear. Knowing that the allowable shearing force in each nail is 740 N, determine the largest permissible spacing s between the nails.

100.49 mm

Explanation:

Given that :

The vertical shear force = 1200 N

Allowable shearing force in each nail = 740 N

From the diagram attached below, We first determine the horizontal force per unit length on the lower surface of the upper flange

where;

Also;

where A = area above (1-1)

Therefore ;

Now; the largest permissible spacing s between the nails.  

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explanation:

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