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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.
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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.
संबंधित प्रश्न
State if the following statement is true or false. Correct the statement if it is false.
A single movable pulley is a pulley that has its axis of rotation fixed.
Explain how a gear system can be used to obtain gain in speed? Given one example.
Define the following term in reference to a gear system for Gain in speed ?
In a gear system, the gear ration of the driving wheel A and driven wheel B is 10:1. To rotate the driven wheel B in the direction of driving wheel A, the driving wheel A is engaged with other wheel C. what should be the gear ratio of the wheels A and C?
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Name the type of single pulley that can act as a force multiplier. Draw a labeled diagram of the pulley mentioned by you.
Write two uses of pulleys. Is pulley a force multiplier?
A type of single pulley is very often used as a machine even though it does not give any gain in mechanical advantage. Name the type of pulley used.
The alongside figure shows the combination of a movable pulley P1 with a fixed pulley P2 used for lifting up a load W.
(i) State the function of the fixed pulley P2.
(ii) If the free end of the string moves through a distance x, find the distance by which the load W is raised.
(iii) Calculate the force to be applied at C to just raise the load W = 20 kgf, neglecting the weight of the pulley P1 and friction.
_______ is a machine made up of wheel and rope.
