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प्रश्न
Give a reason for the following:
In a single fixed pulley, the velocity ratio is always more than the mechanical advantage.
उत्तर
In a single fixed pulley, some effort is wasted in overcoming friction between the strings and the grooves of the pulley; so the effort needed is greater than the load and hence the mechanical advantage is less than the velocity ratio.
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संबंधित प्रश्न
A pulley system with VR = 4 is used to lift a load of 175 kgf through a vertical height of 15 m. The effort required is 50 kgf in the downward direction.
(g = 10 N kg-1)
Calculate
1) Distance moved by the effort
2) Work done by the effort
3) M.A. of the pulley system
4) Efficiency of the pulley system
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Draw a neat labeled diagram of a system indicating the direction of its load and effort
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- mechanical advantage,
- Velocity ratio and
- efficiency of the combination in ideal situation.
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