73.2k views
2 votes
I need help in my physics class and show me how it’s done

I need help in my physics class and show me how it’s done-example-1
User Dmarquina
by
5.8k points

1 Answer

5 votes

If we have the angle and magnitude of a vector A we can find its Cartesian components using the following formula


A_x = |A|cos(\alpha)\\\\A_y = |A|sin(\alpha)

Where | A | is the magnitude of the vector and
\alpha is the angle that it forms with the x axis in the opposite direction to the hands of the clock.

In this problem we know the value of Ax and Ay and we need the angle
\alpha.

Vector A is in the 4th quadrant

So:


A_x = 6\\\\A_y = -6.5

So:


|A| = √(6^2 + (-6.5)^2)\\\\|A| = 8.846

So:


Ay = -6.5 = 8.846cos(\alpha)\\\\sin(\alpha) = (-6.5)/(8.846)\\\\sin(\alpha) = -0.7348\\\\\alpha = sin^(- 1)(- 0.7348)


\alpha = -47.28 ° +360° = 313 °


\alpha = 313 °

Option 4.

User Yuri Kovalenko
by
6.0k points