Forces are what are called vectors having two properties 'amount of'
and 'direction' e.g. an arrow travelling East at 300 fps could be represented
by a vector like -------------------------> where the length of the line
represents the speed and the line/arrow shows the direction of travel.
When forces are added together both 'amount of' and 'direction' of each
individual force affects the resultant total force vector. Suppose we have
a bowstring which as we draw the arrow back has a constant tension. The
force on the arrow changes as we draw it because the the angle the bowstring
makes with the arrow keeps changing as per the diagram.
If instead of bow limbs we ran the bowstring over two pulleys with weights
hung on the end to give a constant string tension then we would get a force
draw curve something like the attached.
Forces are what are called vectors having two properties 'amount of'
and 'direction' e.g. an arrow travelling East at 300 fps could be represented
by a vector like -------------------------> where the length of the line
represents the speed and the line/arrow shows the direction of travel.
When forces are added together both 'amount of' and 'direction' of each
individual force affects the resultant total force vector. Suppose we have
a bowstring which as we draw the arrow back has a constant tension. The
force on the arrow changes as we draw it because the the angle the bowstring
makes with the arrow keeps changing as per the diagram.
If instead of bow limbs we ran the bowstring over two pulleys with weights
hung on the end to give a constant string tension then we would get a force
draw curve something like the attached.