Applied Statics Please help I need to know how to prove that

5 ft Figure P5.7 10 kN 5.8 Figure P5.11 Pulley, radius 1t radius I ft 10 ft 100 lb 10 ft 10 ft igsre P5.8

Solution

the force in DB will be zero because DB is perpendicular to EC and hence there will be no component of DB will be along EC. hence Fdb = 0

similarly when Fdb=0, the Feb = 0, because now no component of Feb will be there along AC.

now since both Fdb and Feb are 0.The Fae = 0 because AE is perpendicluar to EC and hence no compnent of AE is along EC.