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Question : 86 of 160
Marks:
+1,
-0
Solution:
Forces given are as shown
Resloving co,ponents we have,
For equilibrium ;
ΣFy=0 F2‌sin‌60°+F1‌sin‌30°=F3‌cos‌45° ⇒F2×+F1×=F3× ⇒√3F2+F1=√2F3...(i) and
ΣFx=0 F2‌cos‌60°=F3‌sin‌45°+F1‌cos‌30° ⇒F2×=F3×+F1× ⇒F2=√2F3+√3F1...(ii) Subtracting
Eq.(ii) from
Eq.(i) we get,
√3F2+F1−F2=−√3F1 ⇒(√3−1)F2=−F1(1+√3) ⇒F2=F1() ⇒F2=−| F1(√3+1)2 |
| (√3−1)(√3+1) |
⇒F2= or
F2=−F1(2+√3) Now, putting the value of
F2 in
Eq.(i), we get
√3[−F1(2+√3)]+F1=√2F3 F1[−2√3−3+1]=√2F3 F3=√6−√2
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