Advertisements
Advertisements
Question
Fill in the blank:
A pulley is used to change ........................
Advertisements
Solution
A pulley is used to change the direction of effort.
APPEARS IN
RELATED QUESTIONS
State two functions of a machine.
Name a machine to change the direction of force ?
Explain how a gear system can be used to obtain gain in speed? Given one example.
Explain how a gear system can be used to obtain Change in direction of rotation. Given one example.
Define the following term in reference to a gear system of Driving gear ?
Give reason for the following:
The efficiency of a pulley is always less than 100%
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.
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.
In a single movable pulley system, a load of 125 kgf is lifted by an effort of 75 kgf. Find the percentage efficiency of 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?
