Date: Fri 20-Mar-1998

Publication: Bee

Author: JUDYC

Quick Words:

Head-O-Meadow-schools

Full Text:

Exploring The Magic Of Motion In Machines

(with cuts)

What's a machine and how do they work?

Kids at Head O' Meadow were quick to give examples of machines, from a pulley,

a car and a slurpy machine to "the thing you're wearing to make your voice

loud."

But how do they work? Well, that is what they were there to find out. David

Stotz of the Franklin Science Institute told the children, "Every complex

machine has simple machines working in them. And anytime you talk about motion

and machines, you need to discuss motion."

Head O' Meadow students then tested the Newtonian laws of motion, and were

sometimes surprised, sometimes relieved, to see that they did indeed work.

Caitlin Malloy, in the fifth grade, was called up to the stage to show her

strong swing of a baseball bat. Then Mr Stotz told her to do it again, only

this time, standing on a lazy susan.

Missing the friction she had grown accustomed to between her feet and the

floor, she swiveled out of control, in an "equal and opposite reaction" to the

force of her swing. She laughed and wanted to try it again.

Mr Stotz reminded the students that they count on the physical laws of motion,

even without giving them much thought.

He said, "The next time you are at an amusement park, remember that it is only

because of physical laws of motion that you don't go flying out of your seat!"

Machines make use of the physical laws of motion, "so it takes less force to

do work," continued Mr Stotz.

Gina Cavaliere, third grader, was thrilled to lift Josh Tenenbaum, fourth

grader, with one hand and the help of a lever. She learned that by positioning

the fulcrum near to Josh, it became easier to lift his weight.

"If you have a lever that is long enough, one person could lift the whole

school!" exclaimed Mr Stotz.

A pulley system is a simple machine. Mr Stotz had a student lift heavy weights

using pulleys. With a double pulley system it took twice the amount of rope,

but you only have to pull half as hard, explained Mr Stotz.

Wheels are simple machines that reduce friction, but Dustin Welch, third

grader, got to use a machine that practically eliminates it.

Resting on a cushion of air sent through little holes underneath his cart,

Dustin's mini-hover-craft was a breeze to pull around the auditorium.