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urbanupstart
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1. A heavy uniform bar is in equilibrium in the arrrangement shown
(I cannot upload the picture, but the bar is resting on a pivot with two weights at either end. 1.5m to the left of the pivot with 1000N weight at the end. 4.5m to the right of the pivot with a 100N weight at the end)
Question is- what is the weight of the bar to nearest Newton?
3. My attempt so far- anti-clockwise moment of weight is 1.5*1000 = 1500Nm; clockwise moment of right weight is 100* 4.5 =450Nm.
I have never met a question asking me about the bar, but... I reasoned that as the bar is balanced, the clockwise and antclockwise moments must be the same and so
1500Nm + 1.5x = 450Nm + 4.5x (the 1.5x and 4.5x refer to the bar moments/weights)
simplifying to 1050Nm = 3.5x
so x = 350
I have the answer- the bar is 300N,so I was close:) but I cannot get it. Anyone help me through this please?
(I cannot upload the picture, but the bar is resting on a pivot with two weights at either end. 1.5m to the left of the pivot with 1000N weight at the end. 4.5m to the right of the pivot with a 100N weight at the end)
Question is- what is the weight of the bar to nearest Newton?
Homework Equations
3. My attempt so far- anti-clockwise moment of weight is 1.5*1000 = 1500Nm; clockwise moment of right weight is 100* 4.5 =450Nm.
I have never met a question asking me about the bar, but... I reasoned that as the bar is balanced, the clockwise and antclockwise moments must be the same and so
1500Nm + 1.5x = 450Nm + 4.5x (the 1.5x and 4.5x refer to the bar moments/weights)
simplifying to 1050Nm = 3.5x
so x = 350
I have the answer- the bar is 300N,so I was close:) but I cannot get it. Anyone help me through this please?