The fig above shows a uniform wood of weight 200Nand length 50m. It is pivoted at one end and suspended by a cord at the other end at an angle of 30 degrees to the wood. calculate the tension in the cord if the wood is horizontal
Attached Figure / Diagram
A
10N
B
20N
C
100N
D
200N
Verified Correct Answer: D.
Physical Principles & Numerical Solution
Tension in the spring = Tsin 30
Taking a moment about the pivot
200 x 25 = T sin 30 x 50
5000 = T x 0.5 x 50 (since sin 30 = 0.5)
5000 = T x 25
T = \(\frac{5000}{25}\) = 200N
Source: Myschool Past Questions Archive (Record #41722)