People
are usually lifted to the tops of tall buildings by elevators or lifts. An
elevator car is raised by a windlass that is turned by an electric motor.
Tracks keep the car moving in a straight line. A weight balances the weight of
the car so that it is easier to pull up the car. The motor of the elevator can
turn the windlass either way. It can wind up the cable and raise the car. It
can unwind the cable and let the car go down. Electric wires go from the car to
the motor. A person in the car can make it go up, go down or stop by using
switches in the car. You can make a model of an elevator as follows.
 |
| Materials Required |
- Drive
nails through spools into the wooden board.
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| Add caption |
- Take
a cardboard box, say a shoe-box, without the lid. Tie one string to the bottom
of the box and two strings to the top of the box. This box will act as the car
of the elevator.
- Slip
the bottom string of the car over the spools marked 4, 3, 2 and 1. Wind the
string several times around spool 2. Tie its other end at the top of the box.
- Run
the second string from the top of the box over spoois 5 and 6 and finally
fasten it to a weight of about 100 gm to balance the weight of the car.
- You
can put two toys, one of a boy and the other of a girl, in the box as
passengers. Then the windlass (spool 2) with your fingers . The car will go up
and down. You can make this model more attractive by putting it in a model
building constructed of cardboard.
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