How Big is a Newton ?	

All archery bows need an archer to draw them (and hold them pointing in the right direction 
in order to shoot an arrow into a remote target). The archer provides a force to draw the bow.
We can measure the force with a scale, but the scale is calibrated with an object such as an apple 
which has weight because of the effect of gravity.

All mechanical quantities are defined in units of mass, length and time,
not in more desired units of weight, outlook and tv program lengths. 
Mass is a fundamental measure of the amount of matter in an object, 
not how much it weighs on earth, or on the moon ( one sixth as much). 

Weight (W) is measured in England in pounds (lb) and in Europe in kilograms (kg). 
Weight is the force of gravity on an object which is its mass (M) times the acceleration of gravity (g), 
or W = M*g. g = 9.8 m/s/s, meters per second per second, or 32 ft/s/s, feet per second per second 
so it matters what units we use. In England the units of weight are lb*ft/s/s (called the slug), 
and in Europe, kg*m/s/s (called the Newton).

How much force does a small apple  exert on my hand ?
I used a postage scale to find out.
It weighs about 0.104 kg, about 3 oz.  The weight of 0.1kg exerts a downward force due to gravity of 

        		Force  = Mass * gravitational acceleration
		   	        =  0.103 kg * 9.8 m/s/s
			        =  1 kg*m/s/s
			        =  1 Newton.

So, a small apple applies a downward gravitational force of about 1 Newton. Of course, I must exert 
an equal upward force of 1 Newton to hold the apple in my hand. =============
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By comparison, a 5 cm rubber band drawn to twice its original length exerts a force of about 0.5 lb.
So,
		Force = Mass * gravitational acceleration
			= (0.5 lb) 0.227 kg * 9.8 m/s/s
			= 2.22 Newtons.

(c) 2009 Lee F. Donaghey  91115