Advertisements
Advertisements
Question
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.
Solution
VR = 4, η = 90%
(i) MA = VR × η%
`=(4xx90)/100=3.6`
(ii) MA =`"Load"/"Effort"`
∴ Effort =`"Load"/"MA"`
`=300/3.6`
= 83.33 N
APPEARS IN
RELATED QUESTIONS
A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to the same height. Compare the effort applied by them. Give a reason to support your answer.
Define the following term in reference to a gear system for Driven gear ?
Define the following term in reference to a gear system for Gain in torque ?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while ascending a hill ?
Give two reasons why the efficiency of a single movable pulley system is not 100%.
In which direction does the force need to applied, when a single pulley is used with a mechanical advantage greater than one? How can you change the direction of force applied without altering its mechanical advantage? Draw a labelled diagram of the system.
What is the use of a fixed pulley?
What is a pulley?
Draw the diagram of a single movable pulley and obtain its mechanical advantage, velocity ratio, and efficiency.
| 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?
