Types of Pulley: Definition, Mechanism, Advantages & Disadvantages

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Muskan Shafi

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Pulley is a mechanical device that is used to pull or lift heavy objects or loads. A pulley includes a flexible rope/cord/chain/belt being carried on the rim of a wheel. The wheel and rope of a pulley can be of any size and length. A pulley is usually made up of metals. Pulleys help in making various lifting and moving tasks easier.

There are various types of pulleys depending on the purpose they are being used for. Pulleys are classified on the basis of the changes in the direction of the force, changes in magnitude, and changes in both magnitude and force. Fixed pulley, movable pulley, and compound pulley are the three standard types of a pulley.

Read More: NCERT Solutions for Class 11 Physics: Work, Energy, and Power

Key Terms: Pulley, Compound Pulley, Fixed Pulley, Movable Pulley, Wheel, Belt, Block and Tackle Pulley, Swivel Eye Pulley, Cone Pulley


What is Pulley?

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A pulley is a simple mechanical device used to lift objects and loads. A pulley contains a wheel and rope/belt/chain to lift heavy objects. The wheel is fixed to a hinge and rotates on an axle or shaft. 

  • The wheel and rope of a pulley can be of any size and length depending on the heaviness of the load it has to lift.
  • The wheel rotates freely about an axis to its center. One side of the rope is tied to the load/object. 
  • Pulley is generally fixed to hinge and rotated to lift objects.
  • The wheel is called a drum or sheave. 
  • Pulley has different classifications depending on the force and magnitude. 

Pulley

Pulley 


Types of Pulley

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Different types of pulleys are used for different purposes. Various types of pulley systems can make a variety of lifting tasks much easier. The various types of pulleys are as follows: 

Fixed Pulley

  • A fixed pulley has its axle attached to the supporting shaft and is fixed at one place, while the rope moves freely. 
  • When the rope is pulled or pushed and the wheel is rotated, it changes the direction of the force on the rope.

Movable Pulley

  • A movable pulley has its rope fixed to a supporting shaft while the wheel is attached to the object rather than the rope. 
  • When the rope is pulled, the wheel rotates and pulls the object with itself. 
  • This type of pulley requires less work to lift an object and is used in heavy weight lifting. 

Compound Pulley

  • The compound pulley is a mixture of both moving and fixed pulleys. 
  • In this type of pulley system, the object is attached to the wheel of the movable pulley which is further attached to the rope of the fixed pulley. 
  • It is often used on construction sites to lift concrete and in sailboats for lifting heavy objects as it reduces the workload to less than half of the object’s weight.

Types of Pulley

Types of Pulley

Read More: Work, Energy And Power MCQs

Block and Tackle Pulley

  • This type of pulley system play a very crucial role in reducing the work done to move a considerably heavy object. 
  • It is a set of multiple fixed and movable pulleys in a parallel fashion. 
  • The fixed pulleys are fixed and movables are moving. 

Cone Pulley

  • In a cone pulley system, multiple pulleys are arranged at top of each other forming a cone shape. 
  • The pulleys are placed in order of decreasing circumference
  • Examples of this type of pulley can be seen in a bicycle.

Swivel Eye Pulley

  • In this system the block holding the pulley wheel is rotated providing a dynamic rotation. 
  • It is used in lifting objects that require rotation in lifting up. 
  • It is used with wire, fibrous, or nylon ropes.

Fixed Eye Pulley

  • The eye is fixed on the pulley block in this type, thus, it cannot be turned.
  • It uses two or more pulleys and reduces the effort considerably.

Read More: Work, Energy and Power Important Questions


Advantages and Disadvantages of Pulley

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The major advantages and disadvantages of pulleys are as follows:

Advantages of Pulley 

  • The work done required is efficiently reduced in comparison to normal lifting. 
  • The distance between the load and the puller reduces the chances of accidents.
  • It is cost-effective and easy to use. 
  • It's easy to assemble.

Disadvantages of Pulley 

  • It requires a large area for the installation and operation of machinery.
  • Wear and tear of ropes, belts, and chains after consecutive use can cause severe accidents. 
  • It requires regular maintenance and check-up. 

Things to Remember

  • A pulley is a simple mechanical device that is used to lift heavy objects.
  • A pulley is composed of a flexible rope or belt being carried on the rim of a wheel. 
  • The wheel and rope of a pulley can be of any size and length depending upon the purpose it is used for. 
  • There are three standard different types of pulley namely Fixed Pulley, Movable Pulley, and Compound Pulley.
  • Some other types of pulley include Cone Pulley, Swivel Eye Pulley, Block and Tackle Pulley.
  • Pulleys are used on construction sites, raising of curtains on the stage, bicycles, well, etc. 

Previous Years’ Questions (PYQs)

  1. According to the work-energy theorem, the work done… (KEAM)
  2. A ball moving with a velocity of 2 m/s collides head-on with another stationary… (NEET 2010)
  3. On a frictionless surface, a block of mass M moving at speed… (NEET 2015)
  4. The potential energy of a particle in a force field is… (NEET 2012)
  5. A vertical spring with force constant k is fixed on a table… (NEET 2007)
  6. A position-dependent force, F = (7 - 2x + 3x2) N acts on a small body… (NEET 1994)
  7. Water falls from a height of 60 m at the rate of 15 kg/s to… (NEET 2008)
  8. A mass m is attached to a thin wire and whirled in a vertical… (NEET 2019)
  9. A particle of mass 5 m at rest suddenly breaks on its own… (NEET 2019)
  10. An explosion blows a rock into three parts. Two parts go… (NEET 2009)

Sample Questions

Ques. Name the different types of pulleys. (3 Marks)

Ans. Different types of the pulley are as follows: 

  • Fixed Pulley
  • Moving Pulley
  • Compound Pulley
  • Block and Tackle Pulley
  • Cone Pulley
  • Swivel Eye Pulley
  • Fixed Eye Pulley

Ques. Write the disadvantages of a pulley. (3 Marks)

Ans. The disadvantages of the pulley are as follows: 

  • It requires a large area for installation and operation of machinery.
  • Wear and tear of ropes, belts, and chains after consecutive use can cause severe accidents. 
  • It requires regular maintenance and check-up. 

Ques. Write the mechanism of a pulley. (3 Marks)

Ans. Pulley has a wheel with a groove in it which fixes the belt/rope.

  • As the wheel rotates by rotating the central shaft, the rope attached to it moves either upward or downward depending on the direction of movement of the wheel.
  • The power between the axle is transferred to the belt/rope.
  • Long grooves with narrow indentation allow the rope to move.

Ques. How is block and tackle pulley different from compound pulley? (3 Marks)

Ans. A compound pulley is a mixture of fixed and movable pulleys. In a block and tackle pulley, multiple pulleys are arranged in a parallel manner, and in this, the fixed pulleys are fixed and movables are moving.

Ques. What are some real-life uses of pulleys? (3 Marks)

Ans. Some real-life uses of pulleys are construction pulleys, raising of curtains on the stage, bicycle, well, etc. construction pulleys are the most basic and standard pulleys used in heavy weight lifting like concrete.

Ques. A fixed and movable pulley system has 50% efficiency. Find the velocity ratio of the system. (3 Marks)

Ans. Given,

  • Efficiency = 50%
  • Effort = T
  • Load = 4T

Mechanical advantage = Load/Effort = 4T/T = 4

Efficiency = mechanical advantage/velocity ratio

50/100 = 4/ VR

Hence, VR = 8

Ques. Where is tension T and force F acting on the rope? (1 Mark)

Ans. Tension T is in the rope fixed to the ceiling and force F in the rope held in hand.

Ques. Half a force is needed to lift a weight. Explain. (2 Marks)

Ans. There are two forces acting on the rope, force F and Tension T. That means the force is distributed in two directions while pulling the mass (mg) upwards. Hence,

F + T=mg 

2F = mg

F = mg/2

Ques. Define velocity ratio. (1 Mark)

Ans. Velocity ratio refers to the ratio of the distance covered by the effort and the distance covered by the load. 

Velocity Ratio = Distance (effort) / Distance (load)


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CBSE CLASS XII Related Questions

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    An astronomical telescope consists of two converging lenses. One of them of large aperture and large focal length is called objective lens and the other one, of smaller focal length and smaller aperture is called the eyepiece. It is used to see distant objects which are not seen clearly with naked eyes. The image formed by the objective lens acts as an object for the eyepiece and the final image produced by the eyepiece is magnified.


      • 2.
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          • The total charge of the two spheres is conserved.
          • Both spheres attain the same potential.
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          • The final potential of the system equals $\frac{1}{4\pi\epsilon_0} \frac{(q_1 + q_2) (r_1 + r_2)}{r_1 r_2}$

        • 3.
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            • 4.
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                • 5.
                  Read the following paragraph and answer the questions that follow.
                  In an experiment with convex lens of focal length f, the screen is fixed at a distance D from the object. A student slowly moves the lens away from the object towards the screen and finds that she is able to form sharp image of the object for two positions of the lens. The distance between these two positions of the lens is d.


                    • 6.
                      An electric field $\vec{E}$ is established across the ends of a cylindrical conductor of length L and area of cross-section A. Discuss how electrons attain an average velocity, independent of time. Hence, obtain a relation between current in the conductor and this ‘average velocity’ of electrons.

                        CBSE CLASS XII Previous Year Papers

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