Mechanical Engineering - Engineering Mechanics - Discussion
Discussion Forum : Engineering Mechanics - Section 1 (Q.No. 36)
36.
The angle between two forces when the resultant is maximum and minimum respectively are
Discussion:
12 comments Page 1 of 2.
Patrick said:
9 years ago
I disagree. Applying cosine rule R^2 = P^2 + Q^2 - 2PQcos (theta).
Cos0 = 1 (which maintains a negative sign hence obtain a minimum value).
Cos180 = - 1 (which converts the negative sign to positive hence obtains a maximum value).
Cos0 = 1 (which maintains a negative sign hence obtain a minimum value).
Cos180 = - 1 (which converts the negative sign to positive hence obtains a maximum value).
Anil kumar dhaked said:
1 decade ago
From R^2 = P^2+Q^2+2*P*Q*Cos(Theta).
If value of theta = 0° then cos(theta) = 1.
Then R^2 = P^2+Q^2(Maximum).
And
Value of theta =180°Cos(Theta) = -1(negative).
Then R^2 = P^2-Q^2(Minimum).
If value of theta = 0° then cos(theta) = 1.
Then R^2 = P^2+Q^2(Maximum).
And
Value of theta =180°Cos(Theta) = -1(negative).
Then R^2 = P^2-Q^2(Minimum).
Adebc said:
1 decade ago
Resultant of 2 forces will be minimum at 180 degree since the move in opposite direction e.g 4-1=3 but maximum at 0 degree. the same direction
e.g 4+1=5.
e.g 4+1=5.
Keyur Patel said:
8 years ago
There is simple logic when two forces in same direction (0 degree) resultant is max. But they are opposite each other (180 degree) resultant force is min.
(1)
Aravibd said:
9 years ago
If θ = 0.
R = (P + Q)^2.
If θ =180.
R= (P-Q)^2.
Substitute values for p and q. We will get the answer.
R = (P + Q)^2.
If θ =180.
R= (P-Q)^2.
Substitute values for p and q. We will get the answer.
Azaruddin said:
4 years ago
Resultant is Maximum.
Cos(θ) = 1
θ = 0 degree.
Minimum,
Cos(θ) =-1
θ=180degree
Cos(θ) = 1
θ = 0 degree.
Minimum,
Cos(θ) =-1
θ=180degree
(2)
Ashish Mahajan said:
9 years ago
@Anil.
Your explanation is correct, only thing is that,
R = P - Q when theta is 180 degree.
Your explanation is correct, only thing is that,
R = P - Q when theta is 180 degree.
Saraki Yaman Alhaji said:
7 years ago
It should be 180° and 0°.
(1)
Uah said:
7 years ago
Thanks @Keyur Patel.
SHARANABASAVA said:
6 years ago
Thanks @Keyur Patel.
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