Advertisements
Advertisements
प्रश्न
Fig shown a block and tackles system of pulleys used to lift a load.
(i) How many strands of tackle are supporting the load?
(ii) Draw arrows to represent tension in each stand.
(iii) What is the mechanical advantage of the system?
(iv) When load is pulled up by a distance 1 m how far does the effort end move?
Advertisements
उत्तर
(I) 4 stands of tackle are supporting the load.
(ii) correct winding of rope around pulleys, load and effort is as shown:
(iii) M .A = L/E
here,L = 4T, E = T
M.A = `(4"T")/"T"` = 4
(iv) since there are four strings in the block and tackle system, therefore, the velocity ratio of the system is V.R = n = 4
Now, V.R `"d"_"E"/"d"_"L"`
or, `"d"_"E" = 4 xx "d"_"L" = 4 xx 1 = 4"m"`
संबंधित प्रश्न
Is the above pulley system an ideal machine or not?
Solve the following numerical problem.
What effort will be required to lift a load of 500 N by a single movable pulley? [Hint: Mechanical advantage of a single movable pulley is two].
What is a gear system ?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while ascending a hill ?
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?
What is a block and tackle system of pulleys?
The diagram below shows a pulley arrangement :
(i) Copy the diagram and mark the direction of tension on each strand of the string.
(ii) What is the velocity ratio of the arrangement ?
(iii) If the tension acting on the string is T, then what is the relationship between T and effort E ?
(iv) If the free end of the string moves through distance x, find the distance by which the load is raised.
What is a block and tackle system of pulleys?
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
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.
