Vectors: How do you draw this:?

Question

R = A + B - C

A = 30.0m, 30 degrees

B = 40.0m, 130 degrees

C = 35.0m, 310 degrees

My resultant vector looks weird ~_~. I think because I don't know how to draw -C vector

Please help thanks!

Answer 1

R is the Resultant vector;

From a point on a horizontal line, measure 30 deg and lay 30.0m.Draw an arrow at the tip and call it A.

From the arrow tip, measure 130 deg (this is done by taking the 1st quadrant or 90 deg plus 40 deg) and lay 40.0m. Draw an arrow at the tip, call it B.

From the tip of B, take 310 deg.(this is done by starting at the 1st quadrant, taking the 2nd quadrant and the 3rd quadrant, which is 90 deg + 90 deg + 90 deg =270 deg; take a 40 deg to make it 310 deg.). Since vector B is at 130 deg, vector C is located at the 4th quadrant, 10 deg short of overlapping vector B.

Connect the tip of vector C to the origination point. Measure the distance or length of the Resultant R and its corresponding angle.

Resultant R, as it looks, is more than 30 deg., its length, less than 30.0m. An accurate lay out of the lengths and angles will give an accurate length and angle of R!

Answer 2

A negative vector is simply the positive vector rotated around 180 degrees, but keeping the same length.  (Which makes sense because C - C, has to be a vector of zero length)

So -C = 35.0m, 310-180 = 130 degrees.

Its in the same direction as B.

So if you can draw A+B,  just extend B by another 35.0 metres and Bingo!

Answer 3

C makes 310 degrees with x axis.

310 = 360 - 50

Therefore, we can also say that C makes -50 degrees with x axis. Negative angle means clockwise because we take anticlockwise as positive.

So, make vector at angle 50 degrees to x axis but measure 50 deg in clockwise direction.

This is C. Reverse it to get -C