Get premium membership and access questions with answers, video lessons as well as revision papers.

Explain how you can determine the velocity ratio of the following; a) Single fixed pulley b) Single moveable pulley c) A block and tackle

      

Explain how you can determine the velocity ratio of the following;
a) Single fixed pulley
b) Single moveable pulley
c) A block and tackle

  

Answers


sharon
a) Single fixed pulley
4242019951.png
In this arrangement, both the effort and load move through the same distance. Hence the velocity ratio of the system is one.

b) Single moveable pulley
4242019954.png
The load is supported by two sections of the string. If the load is pulled upwards through a distance of 1m, each section of the string also moves through 1m. Hence the effort moves through a total distance of 2m.
Therefore, the velocity ratio of the system = effort distance/load distance =2m/1m =2.

c) A block and tackle
This system comprises two sets; one set fixed and the other moveable. A single string is then passed around each pulley in turn. The arrangement can take several forms depending on the desired velocity ratio. Below is an example:
4242019956.png
In this case, there are four sections of the string supporting the load. Hence, when the load moves upwards through a distance of 1m, each section of the string also shortens by 1m. Therefore, the total distance moved by the effort (string) is 4m.
Thus, V.R of the system= effort distance/load distance =4m/1m =1. Coincidentally, the velocity ratio of the system is the same as the number of sections of the string supporting the load.
sharon kalunda answered the question on April 24, 2019 at 06:57


Next: What are the features of Free Trade?
Previous: Define exceptional development.

View More Physics Questions and Answers | Return to Questions Index


Learn High School English on YouTube

Related Questions