Suppose you first walk 12.0 m in a direction 20 owest of north and then 20.0 m in a direction 40.0osouth of west. How far are you from your starting point, and what is the compass direction of a line connecting your starting point to your final position? (If you represent the two legs of the walk as vector displacements A and B , then this problem asks you to find their sum R = A + B . The two displacements A and B add to give a total displacement R having magnitude R and direction in degrees.

Respuesta :

Answer:

R=19.5m

[tex]\theta[/tex] = 4.65° S of W

Explanation:

Refer the attached fig.

displacement  of the x and y components

x-component displacement is ([tex]R_{x}[/tex]) = [tex]A_{x}+B_{x}[/tex]

= A [tex]\sin[/tex](20°) + B [tex]\cos[/tex](40°)

= -12.0[tex]\sin[/tex](20°) + 20.0[tex]\cos[/tex](40°)

= -19.425m

x-component displacement is ([tex]R_{y}[/tex]) = [tex]A_{y}+ B_{y}[/tex]

=  A [tex]\cos[/tex](20°) - B [tex]\sin[/tex](40°)

= 12.0[tex]\cos[/tex](20°) - 20.0[tex]\sin[/tex](40°)

= -1.579

resultant displacement

R = [tex]\sqrt{R_{x}^{2} +R_{y}^{2} } }[/tex]

=[tex]\sqrt{(-19.425)^{2}+(-1.579)^{2} }[/tex]

=19.5m

[tex]\theta[/tex] = [tex]\tan^{-1}\left | \frac{R_{x}}{R_{y}} \right |[/tex]

[tex]\theta[/tex] = [tex]\tan^{-1}\left | \frac{1.579}{19.425} \right |[/tex]

[tex]\theta[/tex] = 4.65° S of W

Ver imagen empathictruro