Resultant of thirty vectors of a polygon

AI Thread Summary
To determine the resultant of thirty vectors, each with a magnitude of 2N, represented by the sides of a regular polygon, the interior angle is calculated to be 168°. The components along the X and Y axes are derived using trigonometric functions based on this angle. The resultant is found by summing these components and applying the equation R² = Rx² + Ry². A participant expresses concern about the lengthy process and seeks a simpler method for solving such problems. The discussion also touches on the concept that if vectors are arranged head-to-tail in a closed polygon, their sum equals zero.
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University Physics(12th ed) said:
Thirty vectors, each of magnitude 2N, are represented by the sides of a regular polygon taken in order. Determine their resultants.

equation, square of resultant, R2 = Rx2 + Ry2


interior angle of a polygon = (n-2)* 180°/n
= (30 - 2)* 180°/30
= 168°
components on X axis:
Ax1 = 20* cos 168°
Ax2 = 20* cos (168°+168°)
. . . .
Ax30 = 20* cos (168° * 30)

Rx = Ax1 + Ax2 + . . . +Ax30

components on Y axis:
Ay1 = 20* sin 168°
Ay2 = 20* sin (168°+168°)
. . . .
Ay30 = 20* sin (168° * 30)

Ry = Ay1 + Ay2 + . . . +Ay30

thn,
R2 = Rx2 + Ry2





i think we can solve this kind of problem this way, but this process is so lengthy so i am expecting some alternative easy and short way to solve such problems, anyone to help?

The Attempt at a Solution

 
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I'm not sure I understand the problem.

If you add any number of vectors head-to-tail, and the head of the last one meets the tail of the first one, then the sum is always zero.
 
AC130Nav said:
I'm not sure I understand the problem.

If you add any number of vectors head-to-tail, and the head of the last one meets the tail of the first one, then the sum is always zero.

Thanks alot!
 
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