What about the composition of forces

1. F, F 1, F 2, three force loss form loss triangle, accord with triangle cosine theorem

2. The combination of forces is actually vector addition
because force is a kind of vector in space
according to the parallelogram rule or triangle rule of vector addition
in the coordinate system, it can be calculated by coordinates, which is the decomposition calculation of forces, which is exactly the same as the calculation of vectors in mathematics

3. By looking up the table! In fact, you have to remember these special angles when you study physics. The physical angle is 30 °， forty-five °， fifty-three °， sixty °

4. The combination of forces is actually vector addition
because force is a kind of vector in space
according to the parallelogram rule or triangle rule of vector addition
in the coordinate system, it can be calculated by coordinates, which is the decomposition calculation of forces, which is exactly the same as the calculation of vectors in mathematics

5. A2 = B2 + C2-2 * BC * cosa (the first three 2 are squares) in the deformed triangle where your formula is cosine formula, a is the angle, a is the length of the opposite side of angle a, and a, B, C are the length of three sides
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6. Orthogonal decomposition, triangle rule, cosine theorem and so on

7. If there are any two forces F1 and F2, the angle between F1 and F2 is: α Then their resultant force is:
√ the square of F1 + the square of F2 + 2F1 * F2 * cos α

8. The composition and decomposition of forces use the law of parallelogram. The composition of forces is to regard two forces as two sides of parallelogram and draw a parallelogram. Its diagonal is the resultant force of two forces, and the reverse is the decomposition of forces. Do a few more questions will be skilled, in fact, it is not difficult