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प्रश्न
State whether the following statement is True or False.
A pulley changes the direction of force.
पर्याय
True
False
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उत्तर
True.
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संबंधित प्रश्न
Is the above pulley system an ideal machine or not?
Draw a neat labelled diagram showing a pulley being used to lift a load. How are load and effort related in an ideal situation?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while gaining speed on the road ?
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.
Give reason for the following:
In a single fixed pulley, the velocity ratio is always more than the mechanical advantage.
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
Name the type of single pulley that can act as a force multiplier. Draw a labeled diagram of the pulley mentioned by you.
A block and tackle system of pulleys has a velocity ratio of 4.
- Draw a labelled diagram of the system indicating clearly the points of application and directions of load and effort.
- What is the value of the mechanical advantage of the given pulley system if it is an ideal pulley system?
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.
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.
