# Zone d’entraide

### Question de l’élève

Secondaire 5 • 28j

Bonsoir,

Est-ce que vous pouvez m’aider avec cette question? Merci beaucoup!!

Physique

## Explications (1)

• Explication d'Alloprof

Explication d'Alloprof

Cette explication a été donnée par un membre de l'équipe d'Alloprof.

Options
Équipe Alloprof • 28j

The simplest way to answer this question is to solve the equation that establishes that the addition of vectors A and B equals (16,0). The simplest way to do this is to decompose both vectors into their components, and thus, develop two equations:

$$\overline{A}cos(\theta) + \overline{B}cos(\theta) = 16$$

$$\overline{A}sin(\theta) + \overline{B}sin(\theta) = 0$$

Simplifying both equations yields the following:

$$cos(\theta)(\overline{A}+\overline{B}) = 16$$

$$sin(\theta)(\overline{A}+\overline{B}) = 0$$

One can then input the dimensions of both vectors and solve for theta:

$$cos(\theta)(10+10) = 16$$

$$cos(\theta) = 16/20 = 0.8$$

$$\theta = arccos(0.8)$$

$$\theta ≈ 36.9°$$

There you go!

This Alloprof webpage explains vector components:

Don't hesitate to ask for more help!

Poser une question