Steam Boat

Principle:The Archimedes screw is a spiral tube wrapped around a PVC pipe. It works on the principle of when we move the PVC pipe it will lift the water from the reservoir to a higher level.
Applications:
It is used to pump water from relatively shallower depths, viz. river banks.
Items Required to make:
1. PVC pipe 1.6 ft (0.5 m) long
2. Transparent plastic tubing or Copper tube, 1 yd (1 m) long
3. Masking tape
4. Bowls
5. Tub containing water
6. Handle and a Circular Plate or wooden piece
Fun Facts to know:
The archimedes screw can be combined with a Wind mill.In this as the air moves the blades of the windmill, it lifts the water. It is a non-conventional pump working on renewable energy.

Working Of Gears

Principle:
The basic law on which gear works is the constancy of angular velocities or proportionality of position transmission.
Applications:
Gears are used in automobiles and in other puposes in the following way:
1. To reverse the direction of rotation.
2. To increase or decrease the speed of rotation.
3. To move rotational motion to a different axis.
Items Required to make:
1.Empty film rolling boxes(2)
2.Cycle spoke
3.Pins
Fun Facts to know:
Conical gears are used to bend the axis of rotation in a gear train by 90 degrees. The most common place to find conical gears like this is in the differential of a rear-wheel-drive car.