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प्रश्न
Draw a diagram showing a block and tackle system of 4 pulleys.
(i) State, how many strands of tackle support the load?
(ii) Draw arrows to represent tension in each strand.
(iii) Find the mechanical advantage of the system, stating the assumptions made.
(iv) If the load is pulled up by a distance 1m, how much does the effort end move?
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उत्तर
The adjacent diagram shows a block and tackle system of 4 pulleys.
(i) Four strands of tackle support the load.
(ii) The tension in each strand is shown by the arrow marked as T.
(iii) If we neglect the friction of the pulleys and weight of the pulleys in the lower block, then:
L = 4T
and E = T
∴ M.A. =`"L"/"E"`
= `(4"T")/"T"`
= 4.
(iv) If the load is pulled up by a distance 1m, the effort end moves by 4 m.
संबंधित प्रश्न
Fill in the blank:
A pulley is used to change ........................
Answer the following in short.
Explain the various functions that a machine can perform.
Name a machine to change the direction of force ?
Explain the working of a gear system.
Define the following term in reference to a gear system for Gain in speed ?
The mechanical advantage of an ideal single movable pulley is ______.
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
A pulley system has a velocity ratio of 4 and an efficiency of 90%. Calculate:
(i) the mechanical advantage of the system.
(ii) the effort required to raise a load of 300 N by the system.
A ‘block and tackle’ system used 3 pulleys in the lower block and 4 pulleys in the upper block. What is the ‘velocity ratio’ of this system? If the load is to be lifted by a person capable of applying a maximum effort of 1000 N, what is the maximum load than can be lifted under ideal conditions?
The actual maximum load that gets lifted turns out to be 6300 N. What are the values of the actual M.A. and efficiency of the set-up?
