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A bird sits on a uniform rod suspended from vertical wires P and Q.![Image]()
The rod has a weight W and is 15.0 cm long.The weight of the bird is 2W and acts at a distance x from P
What is the value of x when the tension in P is half the tension in Q?
A)7.50cm B)10.0cm C)11.3cm D)15.cm , The answer is C but I cant get to it
The rod has a weight W and is 15.0 cm long.The weight of the bird is 2W and acts at a distance x from PWhat is the value of x when the tension in P is half the tension in Q?
A)7.50cm B)10.0cm C)11.3cm D)15.cm , The answer is C but I cant get to it
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(Original post by shakaib9876)
A bird sits on a uniform rod suspended from vertical wires P and Q.![Image]()
The rod has a weight W and is 15.0 cm long.The weight of the bird is 2W and acts at a distance x from P
What is the value of x when the tension in P is half the tension in Q?
A)7.50cm B)10.0cm C)11.3cm D)15.cm , The answer is C but I cant get to it
A bird sits on a uniform rod suspended from vertical wires P and Q.
The rod has a weight W and is 15.0 cm long.The weight of the bird is 2W and acts at a distance x from PWhat is the value of x when the tension in P is half the tension in Q?
A)7.50cm B)10.0cm C)11.3cm D)15.cm , The answer is C but I cant get to it
Hi,
Welcome to TSR.
Although this question can be solved by setting 2 equations based on the principle of moments about both ends, I would still highly recommend the following (it is more simple IMO, yes it still involve 2 equations)
The resultant force is zero:
total upward forces = total downward forces
This allows finding the tension in P and Q in terms of W.
Spoiler:
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TP + TQ = Weight of rod + Weight of birdsT + 2T = W + 2W
Apply the principle of moment about P to solve for x.
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Sum of clockwise moment about P = Sum of anti-clockwise moment about P
Weight of birds × perpendicular distance from P + Weight of rod × half the length of rod = TQ × length of rod
2W × x + W × 7.5 = 2W × 15.0
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