confirming the principle of parallelogram of forces?

Question

what are the factors that influence the results of resultant on this experiment

Do you mean the geometrical representation of vectors?
On a graph, the resultant is the point where the combined effects of the forces act on an object.


yes i mean that...but i dont seem to understand the factors having an influence in the results, in other words why is ther a percentage error?

Answer 1

Given 2 force vectors, the resultant force vector (which is the sum of the first 2) together with the first 2 and the origin form a parallelogram. In practice, when attempting to compute the resultant force vector from the given 2 force vectors, accuracy drops if the original 2 force vectors are in nearly opposite directions, because small errors can compound to large percentage errors in the resultant force vector. The opposite is true if the original 2 force vectors are in nearly the same direction.

To understand this, let's say that given force vectors A and B have errors a and b, or that the force vectors can be A ± a, B ± b. The sum is A + B ± a ± b, or C + (± a ± b), where C is the nomimal resultant force vector, and the error would be a maximum of a + b. Clearly, C is at maximum if A and B are in the same direction, and minimum if in opposite directions. Let's imagine that A and B are of the same magnitude but in opposite directions. Then C = 0, so the error at maximum is a + b, for the ratio (a + b) / 0 If in the same direction, C = 2A, so the error is at maximum is a + b, for the ratio (a + b) / 2A, which as a percentage is a lot smaller than the former.

Okay, CAT?

Answer 2

Do you mean the geometrical representation of vectors?
On a graph, the resultant is the point where the combined effects of the forces act on an object.

Edit: I honestly did not know there was a percentage of error...All I know is if you add A+B (on a graph) you get R which is a line at the origin of A and B, going between both line A and line B then you add a line from the tip of A to the tip of R and another one to the tip of B to the tip of R and you get a parrallelogram...

Answer 3

Parallelogram Of Forces

Answer 4

I don't know exactly what experiment you did, but there is always experimental error. Do your rulers measure nanometers? Even if they were perfect, Bob, the guy who stamped your rulers, was having a bad day and stamped them at an angle. Are your weights exact? To what decimal place? How do you know? Do you know the guy who drilled the calibrations on them? Was he sober?