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प्रश्न
If the weight of the movable pulley is W, obtain the expression for MA, VR, and efficiency.
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उत्तर
If the weight of the movable pulley with its frame is W, in equilibrium
E = T
L + W = 2T
Or L + W = 2E
⇒ L = 2E − W
MA =`"L"/"E"=("2E"-"W")/"E"=2-"W"/"E"`
VR will remain same, h = `"MA"/"VR"`
`=(2-"W"/"E")/2=1-"W"/(2"E")`
If W << 2E, then 2E = L
Or h = `(1-"W"/"L").`
संबंधित प्रश्न
What is the mechanical advantage of an ideal pulley?
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- How are the magnitudes of L and E related to the tension T1?
- Calculate the mechanical advantage and velocity ratio of the arrangement.
- What assumptions have you made in parts (c) and (d)?
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