| If online homeschool is your choice, I have some great | | | | pulling a weight using a single pulley system. Now pull |
| activities that you will love. Here's one such activity in | | | | the same weight in your triple pulley system. Do you |
| which I will teach you to build your own pulley. | | | | have to use the same force? |
| Hangar Pulley: Make a cut in the center of the base of | | | | You must have noticed that as the number of pulleys |
| a wire coat-hanger (imagine cutting the base of a | | | | increase, it takes lesser force to pull the same weight. |
| triangle). Now take a wooden thread spool and pass | | | | Does this teach you something about how multiple |
| one free end of the recently cut hanger wire all | | | | pulleys are used? |
| through it (left to right) and bend the free end. Now | | | | In the above experiment I have used three pulleys. This |
| take the other free end and pass it in a similar way | | | | means that the weight is distributed among all three |
| through the other side (right to left) and bend the free | | | | pulleys and therefore you will require only one third of |
| end. Make sure that the spool can turn freely. You | | | | the effort to pull the weight. If the object that has to be |
| have now built a pulley. | | | | lifted is 90 lbs, you will have to apply a force equivalent |
| Online homeschool gives you the option to work at | | | | to 30 lbs to lift the object. |
| your own pace, so you must have some fun with your | | | | This is called the mechanical advantage or leverage. |
| pulley. Fix the hanger to a ceiling hook. Take a basket | | | | Mechanical advantage can be determined by counting |
| and tie a strong string to its handle. Pass the rope over | | | | the number of parts the ropes gets divided into (not |
| the pulley and pull the free end of the string to see if | | | | counting the part of the rope you are pulling). What |
| your pulley works. Feel free to put different weights in | | | | does your online homeschool curriculum teach you |
| the basket and try pulling the basket up by pulling the | | | | about mechanical advantage? Do you have access to |
| free end of the string. | | | | any animations to demonstrate the same? |
| Triple Pulley System: You can build this pulley system | | | | If a pulley system has four pulleys the rope is divided |
| in your backyard or below your tree house to get | | | | into four parts (excluding the part you are holding). This |
| food and other stuff to the tree house. Attach two | | | | means that the weight of an object to be pulled is |
| pulleys one above the other on the tree branch. | | | | divided into four parts. Therefore if you want to lift an |
| Attach another pulley with an S-hook to the handle of | | | | object weighing 100 lbs, you would require an effort |
| the basket. Now take a rope and tie one end to the | | | | equivalent to just 25 lbs (100 ÷ 4). In conclusion, if |
| basket handle. Run this rope over the topmost pulley | | | | you want to lift 100 lbs with one hand, you will require 4 |
| and then through the basket pulley and then over the | | | | pulleys. Isn't this interesting? |
| lower pulley. Tie the free end to a pipe in order to | | | | Get your free copy of the "Homeschool Parent's |
| make a handle. | | | | Guide to Teaching Science" which is filled with great |
| Has the number of pulleys made a difference to the | | | | science experiments and activities by clicking the link |
| effort you must put in order to pull an object? Try | | | | below. |