Draw force - not weight

 One more post about basics. In many videos, comments we can see/hear the expression: Draw weight. This is incorrect. The correct one is: draw force. Please use this.

What is force?
In physics, a force is an effect that causes a body to accelerate or change state. Force has direction, which can be any direction. Up, down, left, right, anything.

What is weight?
A special force. Weight is the force, the Earth is pulling the bodies down. Yes, weight is always made by gravitation, and always pointing downwards. 

When we are talking about the strength of a slingshot band, then we are talking about the force we need to hold it, the same force which will accelerate the ball. It is very useful to know this force, to find our favorite setup. We can easily measure this force, by a fishers' scale. This device actually measures force, but fishers use it to measure the mass of a fish, so usually we can see mass measuring units (kg, lbs) on its display. But the measuring unit of force is Newton (N). Primary school phisycs. 

Please remember, on the surface of Earth 1 kilogram mass generates 10 Newton force. So, when you pull the slingshot with the scale, and it displays 3.6 kg, then the force is roughly 36 Newton. Please use Newton, and the expression: draw force. 

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