Advertisements
Advertisements
प्रश्न
Diagram given below shows an arrangement of four pulleys. A load L is attached to the movable lower block and effort E is applied at the free end of the string.
Copy the diagram; and
(i) Draw arrows to indicate tension in each part of the string; and
(ii) Calculate the mechanical advantage of the system.
Advertisements
उत्तर
The following diagram shows a block and tackle system of 4 pulleys.
(i) The tension in each string is shown by the arrow marked as T.
(ii) If we neglect the friction of the pulleys and weight of the pulleys in the lower block, then
L = 4T and E = T
∴ Mechanical advantage =`"L"/"E"`
=`(4"T")/"T"`
= 4
संबंधित प्रश्न
Fill in the blank:
A pulley is used to change ........................
What is the mechanical advantage of an ideal pulley?
What is the justification for using the pulley then ?
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.
Define the following term in reference to a gear system for Gear ratio ?
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?
Give reason for the following:
In case of a block and tackle arrangement, the mechanical advantage increases with the increase in the number of pulleys.
Give a reason for the following:
In a single fixed pulley, the velocity ratio is always more than the mechanical advantage.
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.
| Meera chose to use a block and tackle system of '9' pulleys instead of a single movable pulley to lift a heavy load. |
Why should she connect more number of pulleys in the upper fixed block?
