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Grade 11General Physics

If the resultant of two forces of magnitudes P and Q acting at a point at an angle of 60 degree is ​​root7Q then P/Q is
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Profile image of Rishabh
9 Years agoGrade 11
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2 Answers

Profile image of Vikas TU
9 Years ago
Resultant of two compel given by 
 
R=√(P2 + Q2 + 2PQ cosѳ) 
 
R= √7Q 
 
√7Q =√(P2 + Q2 + 2PQ cosѳ) 
 
Squaring both sides 
 
7 Q2 = P2 + Q2 + 2PQ cosѳ 
 
Ѳ = 60 
 
Cos 60 = ½ 
 
6 Q2 = P2 + PQ 
 
Partitioned by Q2 
 
6 = (P/Q)2 +P/Q 
 
Let P/Q be x 
 
x^2 +x – 6 = 0 
 
x^2 + 3x-2x - 6 = 0 
 
x(x+3)- 2(x+3) = 0 
 
(x+3)(x-2) = 0 
 
x =-3 ,x =2 
 
P/Q =2 
Profile image of Yash Chourasiya
6 Years ago
Hello Student

Please see the solution in the attachment.
643-2368_Untitled.png
I hope this answer will help you.