Advertisements
Advertisements
Question
State whether the following statement is True or False.
A pulley changes the direction of force.
Options
True
False
Advertisements
Solution
True.
APPEARS IN
RELATED QUESTIONS
Explain how a gear system can be used to obtain gain in speed? Given one example.
Give two reasons why the efficiency of a single movable pulley system is not 100%.
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.
The mechanical advantage of an ideal single movable pulley is ______.
The diagram below shows a pulley arrangement.

(i) In the diagram, mark the direction of the forces due to tension, acting on the pulley P.
(ii) What is the purpose of the pulley Q?
(iii) If the tension is T newton, deduce the relation between T and E.
(iv) Calculate the velocity ratio of the arrangement.
(v) Assuming that the efficiency of the system is 100%, what is the mechanical advantage?
(vi) Calculate the value of E
What is a block and tackle system of pulleys?
Give reason for the following:
In case of a block and tackle system, the mechanical advantage increases with the increase in the number of pulleys.
Name a machine which is used to:
change the direction of force applied.
(a) Fig represents an incomplete diagram of a simple string pulley system. Copy this diagram on a new page and complete it and mark where the effort must be applied to lift the load.
(b) What is the velocity ratio of this system?
(c) If the pulley system is 80% efficient and the load is 720 N, then
(i) What effort must be applied to lift the load?
(ii) What work must be done must be done in lifting the load through a distance of 2 m using this machine?

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.
