You can make this very interesting and simple
device at home a hydraulic jack. Jacks are used to lift very heavy loads with little
human effort. They demonstrate a concept of mechanical advantage ,where small forces applied
for large time or distance can be used to lift very heavy loads for small distance. To make
this you need some ice cream sticks, copper wire, needle, syringes, cardboard piece and a flexi
tube. First take a syringe and insert a flexi tube in it. Now put some colored water. We
are using colored water so that we can see the hydraulics. Insert the second syringe
at the other of the flexi tube. Push and pull the plunger to test this part. Now take the
ice cream sticks and make three holes at two corners and in the middle using the needle.
Do this in all eight sticks. Now take the copper wire and weave it, in the middle of
the two sticks. You can make a loop at the end to bind the sticks together. Do this for
all 6 sticks to make a fork or a lazy tong or a snake like structure. See this is the
snake like structure with 6 ice cream sticks. Now take the remaining 2 sticks and attach
at the top of the structure by making a vertical slit in both of the sticks. This is required
for these ice cream sticks to move. And your jack is almost ready. You have to attach the
syringe at the bottom of the ice cream stack. Now push the plunger to see the jack move.
Pull it to get the jack back. Attach some glue at the top of the jack and fix a cardboard.
This is the base on which you can put the load. You can see the concept here that we
are pushing the plunger for small distance and we are lifting the load for a much larger
distance. Actually this is displaying the concept of mechanical advantage but inversely.
To convert this into a real jack where we push the jack for small distance and lift
heavier loads we need to invert the assembly. In this case you can see that we are pushing
the whole ice cream structure for a large distance to lift the load for a small distance.
A very interesting hydraulic device that children can play with.