Suma de vectores usando compoñentes: problemas e solucións

Suma de vectores usando compoñentes: problemas e solucións

1. Tres vectores como se mostra na figura seguinte.

V₁ = 30

V₂ = 30

V₃ = 40

Cal é o resultante vectores.

Coñecido:

V₁ = 30, ángulo entre V₁ e o eixe x = 30^o

V₂ = 30, ángulo entre V₂ e o eixe x = 30^o

V₃ = 40, ángulo entre V₃ e o eixe x = 0^o

Buscase: The resultant vectors

Solución:

The components of vectors :

V_1x = (V₁)(cos 30^o) = (30)(0.5√3) = 15√3. Positive because this vector component points along the positive x axis (rightward).

V_1y = (V₁)(sen 30^o) = (30)(0.5) = 15. Positive because this vector component points along the positive y axis (upward).

V_2x = (V₂)(cos 30^o) = (30)(0.5√3) = -15√3. Negative because this vector component points along the negative x axis (leftward).

V_2y = (V₂)(sen 30^o) = (30)(0.5) = 15. Positive because this vector component points along the positive y axis (upward).

V_3x = (V₃)(cos 0^o) = (40)(1) = 40. Positive because this vector component points along the positive x axis (rightward).

V_3y = (V₃)(sen 0^o) = (40)(0) = 0

Os compoñentes dos vectores resultantes:

V_x =V_1x - V_2x +V_3x = 15√3 – 15√3 + 40 = 40

V_y =V_1y +V_2y +V_3y 15 + 15 = 30

The resultant vector :

2. Two forces perpendicular each other, F₁ = 12 N e F₂ = 5 N. What is the resultant of both forces.

Coñecido:

Forza 1 (F₁) = 12 Newtons

Forza 2 (F₂) = 5 Newtons

Buscase: The resultant vectors (ΣF)

Solución:

ΣF² =F₁² +F₂² = 12² + 5² 144 + 25 = 169

ΣF = √169 = 13 Newton

3. Three vectors,

V₁ = 30

V₂ = 30

V₃ = 40

Determine the resultant vectors.

Coñecido:

v₁ = 30, fai 30^o about the negative x axis

v₂ = 30, fai 30^o about the positive x axis

v₃ = 40, fai 0^o about the positive x axis

Buscase: The resultant vectors

Solución:

Os compoñentes dos vectores:

v_1x = v₁ por 30^o = (30)(0.5√3) = -15√3 (Negative because this vector component points along the negative x axis (leftward))

v_1y = v₁ sen 30^o = (30)(0.5) = 15 (Positive because this vector component points along the positive y axis (upward))

v_2x = v₂ por 30^o = (30)(0.5√3) = 15√3 (Positive because this vector component points along the positive x axis (rightward))

v_2y = v₂ sen 30^o = (30)(0.5) = 15 (Positive because this vector component points along the positive y axis (upward).)

v_3x = v₃ por 0^o = (40)(1) = 40 (Positive because this vector component points along the positive x axis (rightward).)

v_3y = v₃ sen 0^o = (40)(0) = 0

Os compoñentes dos vectores resultantes:

v_x = – v_1x +v_2x +v_3x = -15√3 + 15√3 + 40 = 40

v_y = v_1y +v_2y +v_3y 15 + 15 = 30

O vector resultante:

4. What is the resultant of three vectors as shown in figure below :

Coñecido:

F₁ = 3 Newton, fai 60^o about the positive x axis

F₂ = 3 Newton, fai 0^o about the negative x axis

F₃ = 6 Newton, makes 60^o about the negative y axis

Buscase: The resultant vector

Solución:

Os compoñentes dos vectores:

F_1x =F₁ por 60^o = (3)(0.5) = 1.5 N (Positive because this vector component points along the positive x axis (rightward))

F_1y =F₁ sen 60^o = (3)(0.5√3) = 1.5√3 N (Positive because this vector component points along the positive y axis (upward))

F_2x =F₂ por 0^o = (3)(1) = -3 N (Negative because this vector component points along the negative x axis (leftward))

F_2y =F₂ sen 0^o = (3)(0) = 0

F_3x =F₃ por 60^o = (6)(0.5) = 3 N (Positive because this vector component points along the positive x axis (rightward))

F_3y =F₃ sen 60^o = (6)(0.5√3) = -3√3 N (Negative because this vector component points along the negative y axis (abaixoward))

Os compoñentes dos vectores resultantes:

ΣF_x =F_1x - F_2x +F_3x = 1.5 N – 3 N + 3 N = 1.5 N

ΣF_y =F_1y +F_2y - F_3y = 1.5√3 N + 0 N – 3√3 N = -1.5√3 N

O vector resultante:

5. Two forces, F₁ = 15 N e F₂ = 9 N. The angle between both vectors is 60°. What is the resultant of vectors.

Buscase:

Forza 1 (F₁) = 15 Newtons

Forza 2 (F₂) = 9 Newtons

Ángulo (θ) = 60^o

Quería: The resultant vector

Solución:

6. What is the resultant of three vectors as shown in the figure below?

Coñecido:

F₁ = 20 Newton, angle between F₁ e o eixe x = 0

F₂ = 20 Newton, angle between F₂ e o eixe x = 60

F₃ = 24 Newton, angle between F₃ e o eixe x = 60

Buscase: The resultant vector

Solución:

Os compoñentes dos vectores:

F_1x = (F₁)(cos 0) = (20)(1) = 20. Positive because this vector component points along the positive x axis (rightward)

F_1y = (F₁)(sin 0) = (20)(0) = 0

F_2x = (F₂)(cos 60) = (20)(0.5) = -10. Negative because this vector component points along the negative x axis (leftward)

F_2y = (F₂)(sin 60) = (20)(0.5√3) = 10√3. Positive because this vector component points along the positive y axis (upward)

F_3x = (F₃)(cos 60) = (24)(0.5) = -12. Negative because this vector component points along the negative x axis (leftward)

F_3y = (F₃)(sin 60) = (24)(0.5√3) = -12√3. Negative because this vector component points along the negative y axis (abaixoward)

Os compoñentes dos vectores resultantes:

F_x =F_1x - F_2x - F_3x = 20 – 10 – 12 = -2

F_y =F_1y +F_2y - F_3y = 0 + 10√3 – 12√3 = -2√3

O vector resultante: